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A major cause of error is time stress. Time is often critical, especially in such places as manufacturing or chemical processing plants and hospitals. But even everyday tasks can have time pressures. Add
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Donald A. Norman |
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One negative force is the demands of time: new models are already into their design process before the old ones have even been released to customers. Moreover, mechanisms for collecting and feeding back the experiences of customers seldom exist. Another force is the pressure to be distinctive, to stand out, to make each design look different from what has gone before. It is the rare organization that is content to let a good product stand o..
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Donald A. Norman |
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But in the world of sales, if a company were to make the perfect product, any other company would have to change it--which would make it worse--in order to promote its own innovation, to show that it was different.
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Donald A. Norman |
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complex system: good design requires consideration of the
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Donald A. Norman |
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Cognition attempts to make sense of the world: emotion assigns value. It is the emotional system that determines whether a situation is safe or threatening, whether something that is happening is good or bad, desirable or not. Cognition provides understanding: emotion provides value judgments. A human without a working emotional system has difficulty making choices. A human without a cognitive system is dysfunctional.
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Donald A. Norman |
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At least my computer allows flexibility in type size; most do not.
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Donald A. Norman |
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What appears good in principle can sometimes fail when introduced to the world. Sometimes, bad products succeed and good products fail. The world is complex.
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Donald A. Norman |
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The frequent traveler is continually confronted with this kind of situation: the behavior that is appropriate in one place is inappropriate in another, even in situations that appear to be identical. Known cultural norms can create comfort and harmony. Unknown norms can lead to discomfort and confusion.
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Donald A. Norman |
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4b06f40
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Technology does not make us smarter. People do not make technology smart. It is the combination of the two, the person plus the artifact, that is smart. Together, with our tools, we are a powerful combination.
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Donald A. Norman |
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e5e2c1a
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The major areas of design relevant to this book are industrial design, interaction design, and experience design. None of the fields is well defined, but the focus of the efforts does vary, with industrial designers emphasizing form and material, interactive designers emphasizing understandability and usability, and experience designers emphasizing the emotional impact.
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Donald A. Norman |
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Cognition and emotion are tightly intertwined, which means that the designers must design with both in mind.
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Donald A. Norman |
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Best mapping: Controls are mounted directly on the item to be controlled. * Second-best mapping: Controls are as close as possible to the object to be controlled. * Third-best mapping: Controls are arranged in the same spatial configuration as the objects to be controlled.
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Donald A. Norman |
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Yet surprisingly in this era of screen-based devices, paper tools are still enormously popular and effective, as the number of paper-based diaries and reminders indicates. The
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Donald A. Norman |
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Don't these so-called advances also cause us to lose valuable mental skills? Each technological advance that provides a mental aid also brings along critics who decry the loss of the human skill that has been made less valuable. Fine, I say: if the skill is easily automated, it wasn't essential.
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Donald A. Norman |
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Thus, novices are more likely to make mistakes than slips, whereas experts are more likely to make slips. Mistakes often arise from ambiguous or unclear information about the current state of a system, the lack of a good conceptual model, and inappropriate procedures. Recall that most mistakes result from erroneous choice of goal or plan or erroneous evaluation and interpretation. All of these come about through poor information provided by..
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Donald A. Norman |
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So the hierarchy of goals is roughly: satisfy hunger; eat; cook; read cookbook; get more light. This is called a root cause analysis: asking "Why?" until the ultimate, fundamental cause of the activity is reached."
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Donald A. Norman |
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The action cycle can start from the top, by establishing a new goal, in which case we call it goal-driven behavior. In this situation, the cycle starts with the goal and then goes through the three stages of execution. But the action cycle can also start from the bottom, triggered by some event in the world, in which case we call it either data-driven or event-driven behavior. In this situation, the cycle starts with the environment, the wo..
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Donald A. Norman |
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Warning messages are surprisingly ineffective against mistakes (even nice requests, such as the one shown in Chapter 4, Figure 4.6, page 143). Was this a mistake or a slip? Both. Issuing the "close" command while the wrong window was active is a memory-lapse slip. But deciding not to read the dialog box and accepting it without saving the contents is a mistake (two mistakes, actually). What can a designer do? Several things: * Make ..
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Donald A. Norman |
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Once people find an explanation for an apparent anomaly, they tend to believe they can now discount it. But explanations are based on analogy with past experiences, experiences that may not apply to the current situation. In the driving story, the prevalence of billboards for Las Vegas was a signal we should have heeded, but it seemed easily explained. Our experience is typical: some major industrial incidents have resulted from false expla..
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Donald A. Norman |
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One of my rules in consulting is simple: never solve the problem I am asked to solve. Why such a counterintuitive rule? Because, invariably, the problem I am asked to solve is not the real, fundamental, root problem. It is usually a symptom. Just
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Donald A. Norman |
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It is amazing how often people solve the problem before them without bothering to question it.
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Donald A. Norman |
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This double diverge-converge pattern was first introduced in 2005 by the British Design Council, which called it the double-diamond design process model.
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Donald A. Norman |
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In the university, professors make up artificial problems. In the real world, the problems do not come in nice, neat packages. They have to be discovered. It is all too easy to see only the surface problems and never dig deeper to address the real issues.
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Donald A. Norman |
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Effective design needs to satisfy a large number of constraints and concerns, including shape and form, cost and efficiency, reliability and effectiveness, understandability and usability, the pleasure of the appearance, the pride of ownership, and the joy of actual use. HCD is a procedure for addressing these requirements, but with an emphasis on two things: solving the right problem, and doing so in a way that meets human needs and capabi..
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Donald A. Norman |
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Effective memory uses all the clues available: knowledge in the world and in the head, combining world and mind. We have already seen how the combination allows us to function quite well in the world even though either source of knowledge, by itself, is insufficient.
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Donald A. Norman |
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How do pilots remember? They transform the new knowledge they have just received into memory in the world, sometimes by writing, sometimes by using the airplane's equipment. The design implication? The easier it is to enter the information into the relevant equipment as it is heard, the less chance of memory error. The air-traffic control system is evolving to help. The instructions from the air-traffic controllers will be sent digitally, s..
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Donald A. Norman |
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There are two different aspects to a reminder: the signal and the message. Just as in doing an action we can distinguish between knowing what can be done and knowing how to do it, in reminding we must distinguish between the signal--knowing that something is to be remembered, and the message--remembering the information itself. Most popular reminding methods typically provide only one or the other of these two critical aspects. The famous "..
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Donald A. Norman |
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As we just discussed, reminders provide a good example of the relative tradeoffs between knowledge in the world versus in the head. Knowledge in the world is accessible. It is self-reminding. It is always there, waiting to be seen, waiting to be used. That is why we structure our offices and our places of work so carefully. We put piles of papers where they can be seen, or if we like a clean desk, we put them in standardized locations and t..
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Donald A. Norman |
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What happens when we rely too much upon external knowledge, be it knowledge in the world, knowledge of friends, or knowledge provided by our technology? On the one hand, there no such thing as "too much." The more we learn to use these resources, the better our performance. External knowledge is a powerful tool for enhanced intelligence. On the other hand, external knowledge is often erroneous: witness the difficulties of trusting online so..
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Donald A. Norman |
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fbb86eb
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Technology does not make us smarter. People do not make technology smart. It is the combination of the two, the person plus the artifact, that is smart. Together, with our tools, we are a powerful combination. On the other hand, if we are suddenly without these external devices, then we don't do very well. In many ways, we do become less smart.
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Donald A. Norman |
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When things work, we are informed, comfortable, and effective. When things break, we may no longer be able to function. This dependence upon technology is very old, but every decade, the impact covers more and more activities.
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Donald A. Norman |
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You are designing for people the way you would like them to be, not for the way they really are." When"
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Donald A. Norman |
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Semantics is the study of meaning. Semantic constraints are those that rely upon the meaning of the situation to control the set of possible actions. In the case of the motorcycle, there is only one meaningful location for the rider, who must sit facing forward. The
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Donald A. Norman |
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One way of overcoming the fear of the new is to make it look like the old. This practice is decried by design purists, but in fact, it has its benefits in easing the transition from the old to the new. It
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Donald A. Norman |
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Basically, it means that when searching for the reason, even after you have found one, do not stop: ask why that was the case. And then ask why again. Keep asking until you have uncovered the true underlying causes. Does
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Donald A. Norman |
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We need to remove the word failure from our vocabulary, replacing it instead with learning experience. To fail is to learn: we learn more from our failures than from our successes.
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Donald A. Norman |
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Predicting technology is relatively easy compared to predictions of human behavior, or in this case, the adoption of societal conventions. Will this prediction be true? You
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Donald A. Norman |
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What is natural depends upon point of view, the choice of metaphor, and therefore, the culture. The design difficulties occur when there is a switch in metaphors. Airplane
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Donald A. Norman |
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Lego Motorcycle. The toy Lego motorcycle is shown assembled (A) and in pieces (B). It has fifteen pieces so cleverly constructed that even an adult can put them together. The design exploits constraints to specify just which pieces fit where. Physical constraints limit alternative placements. Cultural and semantic constraints provide the necessary clues for further decisions. For example, cultural constraints dictate the placement of the th..
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Donald A. Norman |
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The visible affordances of the pieces were important in determining just how they fit together. The cylinders and holes characteristic of Lego suggested the major construction rule. The sizes and shapes of the parts suggested their operation. Physical constraints limited what parts would fit together. Cultural and semantic constraints provided strong restrictions on what would make sense for all but one of the remaining pieces, and with jus..
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Donald A. Norman |
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Alas, sometimes clever people are too clever for our good. Some well-meaning plumbing designers have decided that consistency should be ignored in favor of their own, private brand of psychology.
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Donald A. Norman |
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human error usually is a result of poor design: it should be called system error. Humans err continually; it is an intrinsic part of our nature. System design should take this into account. Pinning the blame on the person may be a comfortable way to proceed, but why was the system ever designed so that a single act by a single person could cause calamity? Worse, blaming the person without fixing the root, underlying cause does not fix the p..
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Donald A. Norman |
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Why does inelegant design persist for so long? This is called the legacy problem, and it will come up several times in this book. Too many devices use the existing standard--that is the legacy. If the symmetrical cylindrical battery were changed, there would also have to be a major change in a huge number of products. The new batteries would not work in older equipment, nor the old batteries in new equipment. Microsoft
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Donald A. Norman |
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We are unaware of them. As a result, many of our beliefs about how people behave--including beliefs about ourselves--are wrong. That is why we have the multiple social and behavioral sciences, with a good dash of mathematics, economics, computer science, information science, and neuroscience. Consider the following simple experiment. Do all three steps: 1. Wiggle the second finger of your hand. 2. Wiggle the third finger o..
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Donald A. Norman |