In chapter one, Norman introduces the ideas of affordances, conceptual models, mapping, and feedback. Affordances are simply what users think an object might do. Conceptual models are users' mental image of how a device should perform. Mapping stresses the importance of location and orientation of devices so that their use is obvious. Feedback allows users to gain valuable information back from a device they are interacting with. In chapter two, the author discusses device users blaming themselves, device users blaming the wrong cause, the Gulf of Evaluation and Execution, and the Seven Stages of Interaction. Users often blame themselves if they cannot figure something out that they think should be easy. Users often blame random events if they cannot find a true source of trouble. The Gulf of Evaluation is the difference between the designer's mental design model and the user's conceptual model. The Gulf of Execution is the difference between the options a user thinks a device should have and the options actually available. In chapter three, Norman explains the difference between knowledge in the head and knowledge in the world. A truly efficient design will maximize the design of the device by including both types of knowledge and natural mapping. In chapter four, the author explains how physical, cultural, and logical constraints allow users to accurately understand a device with minimal memorization or training. In chapter five, we study the differences between slips and mistakes, and how the difference can be considered when designing devices/objects. In chapter six, the idea of evolutionary design is introduced and we begin to relate it to common design problems. In chapter seven, Norman summarizes the first six chapters into a guide of sorts, highlighting the main "rules" that will help designers create more user-friendly devices.
I really enjoyed reading this book, because it made me stop and think about everything around me. Literally. It is easy to find objects that appear to have been designed very poorly, with little consideration for how a user would actually interact with it. The references to outdated technologies provided comical relief when trying to read mass amounts of content in short amounts of time. Below I spend some time discussing each
chapter in further detail.
Chapter 1: The Psychopathology of Everyday Things
Introduction
In chapter one of “Design of Everyday Things,” the Author, Donald Norman, presents several examples of objects with exceptionally bad design flaws. For example, the author describes a high-tech phone, capable of call-back and redial features, but illustrates how the designers fell short. The idea behind presenting the design flaws is to provide readers with a series of guidelines that will allow for the design of easily understandable and intuitive devices.
Affordances
The first key concept highlighted in chapter one is the idea of “affordances.” Affordances are the perceived possible uses of an object. More plainly, an affordance is how a person expects to interact with an object. For example, a poorly designed knob could imply that a user could push it, instead of correctly operating the knob by turning it. In this example, the designer could add ridges or grooves around the edge of the knob in order to imply that you will rotate the device. Also, they could make buttons more shallow, so that it would be difficult to try and rotate them. This is an example of how to take advantage of affordances in order to make a superior designed object.
Conceptual Models
The next key concept highlighted in chapter one is the importance of a good conceptual model. A conceptual model is how a potential user imagines that a device will operate. The example used in the book is a bike, which is really two bikes facing each other and sharing the front tire. Users should know that the device will operate poorly because they will try to form a conceptual model in their mind. If each half of the object (left and right) operate similar to a normal bike, then when two users operate the bike pedals, the force generated by each user will directly oppose the other user. This conceptual model will provide potential users with a base idea of how to use an object. A poorly designed object will either have a conceptual image that raises concerns regarding its operation or does not provide clues that will help the users form a conceptual model at all.
Mapping
The third key concept from chapter one is mapping, which stresses the benefit of spatially arranging objects in such a way that users will intuitively know what the objects purposes are. A good example of mapping is placing the controls for power windows in an automobile on the inside door panels versus the center console. This location implies that it does some action to some object located on or near the door. You can further improve this design by having the power window control be an up-down switch which will provide users with an excellent conceptual model. Another mapping example is when cell phone designers put the volume control rocker on the side of a cell phone. This spatial location allows the users to still operate the call volume while having the phone pressed against their faces. The fact that the control is a rocker switch, which operates up-and-down, only enhances the user’s conceptual model of which direction they should push the rocker if they want the volume to increase, or go up.
Feedback
Finally, the idea of feedback enhances users interaction with objects by confirming their actions by providing a logical response. A very simple example of this is for a device to beep when a user presses a button. If the device did not provide this feedback, then some users would question whether they actually pressed the button down enough or not. Another similar example is for touchscreen devices to provide tactile feedback to users. In this example, I also wish that there was a way to provide visual feedback signaling the exact location of the touch input.
Chapter 2: The Psychology of Everyday Actions
Blaming Yourself
Donald Norman stresses one main point repeatedly in chapter: “Don’t blame yourself for bad designs.” Norman explains that users are likely to blame themselves and feel ashamed if they cannot figure out how to perform an action that they believe should be easy. However, most of the time this confusion is due to poor designs that often lead to faulty conceptual models forming in users’ minds. He further states that most people feel this same confusion and embarrassment, but are more likely to still blame themselves than to blame the design. This is illustrated using an example of a “return” key versus an “enter” key on a keyboard. This example is obviously not the best example anymore, because those two keys have been phased out and we are left with one simple “enter” key.
Blaming the Wrong Cause
Along with blaming ourselves, humans tend to be explanatory creatures, looking to find an acceptable explanation for any action that defies our previous expectations. Norman explains this using an example of a co worker whose computer is having problems where they connect to a library catalog and then their computer died. The user associated the two events as cause and effect, because they did not have another suitable explanation. In reality, the problem had nothing to do with the library catalog, but this story helps explain why humans might look to pass the blame onto something convenient.Another important idea that the author introduces is the idea of blaming the wrong cause in social situations as well. Norman mentions that if we personally succeed, then we attribute the success to hard work and perseverance. However, if someone else succeeds at a venture, then we are more likely to blame the environment, casting the achievement off as good fortune. Inversely, if we personally fail at something, we will blame it on the environment, claiming bad luck. Furthermore, if someone else fails at something, we will say that it is because they did not try hard enough, ignoring any part the environment might have played in the situation. I find this point very interesting, because this is definitely how I see personal successes and failures, as well as other peoples’ successes and failures. This makes me realize that I should try to be more understanding of what all contributes to a given situation.
Seven Stages of Action
Norman also discusses what he believes to be the seven stages associated with action. First, “perceiving the state of the world” is when a person observes something in their environment. Second, “interpreting the state of the world” is when the person attempts to explain what they are perceiving in the world. Next, “forming the goal” establishes the purpose for an action, or what we want. Then, “forming the intention” is when an individual plans to do something to achieve a goal. Next, “specifying an action” is the process of refining the results of “forming an intention” so that a single action, or set of actions, is outlined. Then, “executing an action” is when the person actually carries out the action, or set of actions planned. Finally, “evaluating the outcome” happens when the individual reflects on the effects of their action.
The Gulf of Execution and Evaluation
The final points that Norman makes in chapter 2 revolve around the idea of a “Gulf of Execution” and a semi-related “Gulf of Evaluation.” In the first case, the “Gulf of Execution” describes the gap between the actions that a user expects a device to have and the actual actions provided by the device. Another way to think about this is usability. Are users able to use a device without strenuous effort being applied to learning the device’s actions? Next, the “Gulf of Evaluation” describes the gap between a user being able to visualize how a device will operate and the intended conceptual model. Is the user able to properly and accurately form a realistic, working conceptual model in their mind? If so, then the “Gulf of Evaluation” is minimized in the particular situation.
Chapter 3: Knowledge in the Head and in the World
Information is in the World
Whenever knowledge is in an environment, the need for people to memorize it diminishes. One really good example that Norman makes in chapter 3 is U.S. coins. If you were asked to correctly draw a U.S. penny, you would most likely place key things in wrong locations. You may even draw the head facing the wrong way. This does not mean that every singled one of us is incapable of distinguishing a penny from a dime, or a nickel, or a quarter. The idea is that when knowledge is stored readily available in the surrounding environment, the need to memorize it vanishes. An example of situations that wreak havoc in this situation would be if two coins, very different in value, were made in similar shape, size, and color, because there would be a high chance that they would be mixed up from time to time.
The Power of Constraints
Another thing that aids in our ability to process information and respond accordingly without having to fully memorize the information is situational constraints. For example, the English language and our past experiences with conversations and stories, allows us to accurately guess what word should come next when trying to remember the lyrics to a song or the words to a poem. For example, if I were to say “The color of that ball is ______,” one would expect the next word to be a color. The word “jump” or “finish” do not make sense in the sentence. Furthermore, if I were to quote a poem with adequate rhyming, you would be given further constraints. For example, “Roses are red, violets are blue, sugar is sweet, and so are ____.” Given this poem, you would not only be able to constrain the possible word choices by sentence structure, but also by rhyming, because the appropriate word is expected to rhyme with “blue.”
Memory is Knowledge in the Head
However, for situations where environmental knowledge and logical constraints cannot be applied to simplify a situation, one must rely on memory. It is important to distinguish between two main types of memory: long term memory and short term memory. Long term memory is when a person must remember something for extended periods of time. Long term memory usually takes more effort to store information and takes more effort to recall the memory as well. Inversely, short term memory is best used to store a seven digit or less number, or a short sentence or phrase, for a very short amount of time. Normally, short term memory is lost as soon as a person’s attention is directed somewhere else, so it is important to not get distracted.Furthermore, there are three structures of memory: "Memory for arbitrary things," "Memory for meaningful relationships," and "Memory through explanations." The first memory structure describes memorizing something without being able to relate it to some relationship to an existing piece of knowledge, or without logical or physical constraints. The second memory structure type is a way of memorizing something based on relating it to something else that is either common knowledge or environmental knowledge. For example, remembering that the left light switch controls the left light and vice versa for the right light. This is easy to remember because we relate it to a well known, easily related piece of knowledge. Finally, the third memory structure type stores information by figuring out logical or physical constraints that will help shape our understanding of the object or idea in question. The example that Norman uses for this memory structure type is the sewing machine bobbin that appears to "magically" intertwine the top and bottom strands of thread. After explaining how the bobbin actually accomplishes this "magical" feat, it becomes much easier to remember, because we have placed logical constraints on the information.
Natural Mappings
The explanation of memory that we have been discussing in chapter three brings us back to the idea of natural mapping. An object with good natural mapping allows the information related to the use or functionality of the object to be stored in the environment. This means that the user will not have to worry about arbitrarily memorizing its instructions for use. However, it is important to weigh the benefits of knowledge in the world versus knowledge in the head. For example, knowledge in the world requires no learning, but is only available in a particular environment. On the other hand, knowledge in the head requires learning, but it can be recalled regardless of environmental hints.
Chapter 4: Knowing What to Do
Physical Constraints
Continuing the trend of discussing design principles, Norman delves further into the idea of constraints. Physical constraints are a very powerful form of constraints. When faced with an object, we can gain insight into the intended functionality of the object by simply observing the physical constraints. Norman uses a Lego set as an example, but the thing that kept coming to my mind is the toy for babies/toddlers where you have to put blocks of different shapes through holes of different shapes on a ball. Through physical constraints, most of us know that the circle block goes with the circular hole, the triangle block goes with the corresponding triangular hole, and so on. No one needs to explain this to us, we try once or twice and learn that physical constraints matter.
Cultural Constraints
Another important type of constraint is cultural constraints. Here we use previous knowledge of our cultural norms in order to fill in the blanks. For cultural constraints, Norman's Lego example works perfectly. When English speaking Americans go to put the pieces with "Police" written on the sides, the are able to determine that the piece should be oriented so that the word will be right-side-up, even if the piece can also physically fit up-side-down.
Logical Constraints
The final major type of constraint is logical constraints, which allow users to use logic to determine descriptions about an object. Logical constraints tend to be very similar to cultural constraints, because they are both forms of previous knowledge, however logical constraints should bridge cultures. Norman continues with the Lego example to illustrate logical constraints. Logic dictates that all pieces of the Lego kit be used. However, I think that this example is lacking for a true explanation of logical constraints. This is because Lego kits are notorious for including extra parts. A better example of logical constraints is if you take apart your blender, when you put it back together there should be no extra parts. I believe that this example works better because we know that there should be no extra parts from the beginning, whereas in the Lego example, the only way we would know if the kit contained extra parts would be if the instructions contained a parts list. This is not the case. Another similar example would be IKEA furniture, but my last run-in with IKEA furniture has left me to traumatized to explain further.Chapter 5: To Err is Human
Slips vs Mistakes
When categorizing errors it is important to distinguish from slips and mistakes. A slip is an accidental, automatic or routine behaviors. Slips tend to occur when two actions are very similar, for example storing your eggs in the pantry instead of the fridge. A mistake happens when a person consciously decides something and then is wrong. For example, I cannot remember whether I should turn left or right here, but my ultimate destination is to the east of my current location, therefore I will take the turn closest to east. If this turn ends up being the wrong direction, I have made a mistake.
Within the category of slips, there are six subcategories. The first subcategory is capture errors, which are when the beginning of two actions are similar, but you accidentally transfer to the wrong action. For example, when counting time versus money we restart time after the sixtieth count, whereas we restart the count for money when after the one-hundredth count. The next slip subcategory is description errors, which happen when an action can be performed on two similar objects and we end up mixing up the objects. The example that comes to my mind is holding a non-edible object in one hand and an edible object in the other, and then trying to eat the non-edible object because the action required to put it in your mouth is so similar for both objects. The third slip subcategory is data-driven errors, which are when someone accidentally mixes up two pieces of data that they are attempting to use for something. For example, if someone is speaking a sentence that they are thinking in their head, but because they are looking at a sign that says "Frank's," they accidentally say "Frank's" in their sentence. The fourth slip subcategory is associative action errors, which happen when which is very similar to data-driven errors, but instead of the distraction being external, it is reversed. You might be performing a physical action, when you accidentally mix up what you are thinking into the action you are performing. The fifth slip subcategory is loss-of-activation errors, which happen when you start to do something and either forget the details of what you are doing, or forget that you are doing anything particular at all. This is one of the most common slips in my life. I will go towards the backdoor to let my dog in, but I forget and end up grabbing the laundry out of the dryer, which happened to be on my way. Finally, the last slip subcategory is mode errors, which are when different modes of operation, which have different associated actions, get switched in our minds and cause us to do some unintentional action.
Mistakes tend to be much easier to analyze because they are usually more simple. If you evaluate a situation wrong, collect the wrong data, or aim at the wrong goal, then there is a good chance that you will make a mistake. However, it is important to consider both mistakes and slips when designing an object. If you can account for some of the types of slips or mistakes mentioned, then you can create a device that is more useful and intuitive. There are many different ways to accomplish this, but the main one that stuck out to me was forcing functions. For example, if you are designing a website form needing a phone number, check the format of the phone number and don't let the user move on until the format matches the desired format. This should prevent users from accidentally entering another number, for example their social security number.
Chapter 6: The Design Challenge
Evolutionary Design and the Typewriter
When a typewriter inventor, Mr. Sholes, was deciding on the intricacies of his device he used multiple sources for feedback. Firstly, he gathered responses and reviews from potential everyday users such as writers. Secondly, there are physical constraints. He experimented with many different keyboard designs until the QWERTY keyboard was chosen as the victor. One reason for the need of multiple rows is so that buttons directly next to each other would not cause interference with the typebars in the background. The QWERTY keyboard became the standard for keyboard layouts all across the world and is still used today, even though the physical constraint no longer exists. There is another popular keyboard format, called DVORAK, attempts to improve upon the QWERTY keyboard by arranging the keys in such a way that the most commonly used keys are the home keys and the least used keys are the farthest away from the home keys. The lesson here is that once a product is designed, accepted as satisfactory, and gained popularity, then it would not be worth it to further change it.
Design Problems
There are many different problems that arise when a designer is created an item. First off, there is an ever-going battle between usability and aesthetics. If one dominates the other, then problems pop up. If an item is so aesthetically pleasing that no one can figure out how to use it, then the designer failed. Conversely, if an item is designed so well that it is extremely easy to use, but it looks horrible, then the designer failed. The problem is that most consumers do not focus on usability when they are shopping for something. Price and aesthetics are the first things noticed. Also, designers may think that their device is easy to use, but sometimes that is because as they design and test the device, they become an expert. It is never a good idea to test something on experts alone. Finally, designers have to please their clients, because they are the ones paying the bills. However, the client may not be a good test user either, so designers should be careful in these situations as well.
Chapter 7: User-Centered Design
Seven Principles for Transforming Difficult Tasks into Simple Ones
1) Use both knowledge in the world and knowledge in the head
2) Simplify the structure of tasks
3) Make things visible: bridge the gulfs of Execution and Evaluation
4) Get the mappings right
5) Exploit the power of constraints, both natural and artificial
6) Design for error
7) When all else fails, standardize
*NOTE: I borrowed these verbatim from the book because I thought Norman did a great job summarizing the points made in this book and I would like to use them in my future designs.
Three Aspects of Mental Models
The design model is how the designer/engineer intended the object to be. The conceptual model is how the users actually mentally perceive the objects actions. If an object is designed well, there will be very little difference between the design model and the conceptual model. The system diagram is best described as the visual portion of a device.
Standardization
There are a few things to keep in mind when discussing standardization. First, when done properly, standardization can reduce ambiguity. However, when standardizing you must be careful that you do not lock-in a standard too early and get stuck with primitive technology. Unfortunately, this explanation does not give any hint at what the right time will be. There will be some arbitrary point somewhere on the timeline of a technology's development when little future change is expected to occur, this is the point that I would argue is the best point for standardization.
5 Examples of Bad Design
1) Road bike gear shifters & brake levers:
Modern road bikes have some good design principles built in to the
the gear shifters and brake levers, but the designers still provide no clear indication of which side does the front brakes or rear brakes.When looking at the bike, you can clearly gain a decent conceptual image, but you still have no way of knowing which lever corresponds to which brake. They also incorporate the shifters into the brake lever, so that you can push the lever to the inside and it will shift for you. This is a great idea and very convenient, unfortunately the ambiguity regarding the front/back breaks makes this an overall bad design, requiring the users to memorize the functionality, because there is not appropriate mapping.
2) Door Lock with ID Scanner
The main problem with this door lock with integrated ID scanner is that there are four possible ways to insert your ID card. Even if you are smart enough to guess that the scanner would need more area than possible in the part in front of the slot, you would still have two options to choose from. I believe that this could be clarified by adding an arrow on the side requiring the magnetic strip, or if they added a picture of the card oriented the right way. Although, the design does give decent feedback by beeping and lighting either a red light for a bad card or a green light for a good card.
3) 1996 VW GTI Gear Shifter
The peculiar thing about this gear shifter is that the reverse gear is left and up, which is easily shown on the label on top of the shifter. So, at first glance this object appears to be designed well, with a label allowing users to create a conceptual model in their minds. However, I kept having trouble getting the transmission to go into reverse. I would push the right direction, but it seemed like something was wrong because I would have to force it into reverse. Later on I realized that in order to get it into reverse, all you have to do is press down on the shifter and then push it to the left and then up. The designers probably did this to prevent someone putting the transmission into reverse instead of first gear, which is usually to the left and up. However, due to the lack of sufficient labeling and knowledge in the environment, I was not able to figure out how to use it easily.
4) USB Plug
This one really needs no introduction. USB plugs are ambiguous and frustrating. Even if you use USB plugs all of the time, it is easy to mix up the orientation because there is no evidence of correct orientation. Technically there is physical constraints in place because if you try to insert the plug in the wrong orientation, it will not go in. However, I believe that if the USB designers would have provided a physical distinction in the plug shape, then it would save us all a lot of time. Examples of physical modifications possible are miniUSB and microUSB shapes, which provide sufficient mapping and logical/physical constraints so that users rarely mix up the orientation.
5) Weird Water Fountains
These water fountains can be found in the A&M Rec Center and G. Rollie White Colosseum, however I have never once seen them used. When I first saw them I noticed the way to turn on the water, which is done by either pressing the bar or rotating the knob. I also noted that there was a pipe on the top of the dish, which I assumed as for filling water bottles until I tried and realized that the water only comes out of the back of the pipe and trickles down the basin. The only possible solution that I could come up with is that this is a "spitting" fountain, which still makes no sense. There are clearly physical constraints in place, but I cannot figure out how to use this device. There is no labeling, no cultural knowledge, no environmental knowledge, and no logical assumptions easily made.
5 Examples of Good Design
1) Doorbell
Doorbells are a great example of a simple, but good design. The long flat shape of the button, without ridges or edges, implies push. Also it is visible, located at an average eye height, and is mapped well by placing it near the door.
2) Truck Dome Lights
My truck's dome lights provide a really nice example of a simple, but good design. There are two buttons corresponding to two lights. It is easy to tell that the buttons are indeed buttons, because there are not many other options for interaction. They do not stick out enough to try and rotate them or pull them. Also, the buttons are mapped well, by placing them next to the light that they each operate. The buttons also provide great feedback by physically clicking when they are pressed, not to mention the lights comes on.
3) Flashlight
This flashlight shows great design principles. There are obviously two ways to interact with the flashlight, one is to press the button which is conveniently located near the lens to imply that it toggles the light itself. The other function is the rear cap is ridged to imply that the only way of physically interacting with the end is to twist it. The button also provides great feedback by physically clicking when it is pressed, not to mention the light comes on.
4) Mirror Controls
While in my truck, I noticed that the mirror control was very easy to use due to good design. The top rocker can be pressed left or right. The bottom directional pad can go left, right, up, or down. From the mapping, labeling, physical constraints, and cultural constraints it is easy to deduce that if you push the rocker left you will control the left mirror and vice versa. Once a mirror is selected, then the directional pad can be used to adjust the orientation of the mirror. Even more, both sets of buttons provide ample amounts of feedback. Firstly, the top button stays left or right when you push it, but the directional pad springs back to its normal position.
5) Beer Taps
While I was sitting there thinking of what my last object should be, it jumped right out at me! Beer taps are a great example of design because they have a long lever on top, which implies that it should be pulled. The open, tube-shaped tip underneath the lever hint that something will come out of them when the lever is pulled. Using my cultural and logical knowledge I am able to deduce that beer should come out of the hole if the lever is pulled, since these are after all located in a bar. Great design.
Nice blog post. I can tell you put a lot of thought into each one of your design choices. I have also seen that strange water fountain in the REC and I would love to know what its used for.
ReplyDeleteEach design example did let me think more about how to design a simple product. The reflections seems to me more like a summary rather than a reflection
ReplyDeleteYour chapter summaries were phenomenal. The best I have seen thus far. If I could award bonus points here, I would. Your book summary was also very articulate.
ReplyDeleteWhile I applaud you on the chapter reviews, did they really have to be a page a piece? This was a huge amount to read. On the other hand, I greatly enjoyed your descriptions of good and bad designs. I have to agree that the door scanner is a terrible design.
ReplyDeleteYour chapter summaries are some of the best I've read. Examples were good and overall reaction was well written.
ReplyDeleteYour book/chapter reactions were summaries and provided little to no real reaction to what you had read. Other than that, your design examples were excellent and evaluated well. Also, the picture of the truck interior looks like a face.
ReplyDeleteYour reactions seems to be more summaries than reflection. Your examples of good and bad design are excellent. I've seen multiple post on the bike brakes and gear shifting and am convinced they could be designed a bit better for people new to them to understand. As a rider who typically rides faster than what's probably safe around campus, I feel that once learned though, the function of these work really well.
ReplyDeleteThe reactions were basically just summaries not really how you reacted to the chapter. Other than that the examples were good and explained very well
ReplyDeleteYour summaries were so thorough! I would have liked to hear more of your thoughts on each of the chapters, though. I agree that the Lego example was a little lacking for the purpose of explaining logical constraints - isn't that the point of Legos, to build whatever you want with them? I suppose with a Lego kit, you have more constraints, but there is still a lot of room for modification. I also really appreciate your beer tap example. Isn't it also convenient how they are all nicely labeled?
ReplyDeleteYour design examples were great, but the books reactions contained little to no personal thoughts on the topics presented, and dragged on quite a bit as well.
ReplyDelete