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The idiotic practice of "let's say 30 knowing that people will drive 40 anyway" is self-defeating.). Another common example is driving a rental car whose headlights and windshield wiper knobs are in the opposite position than those in your normal car - such that when it begins to get dark, you reach over and turn on the windshield wipers. People circumvent or ignore safety procedures in order to get things done faster to meet demands. In other instances, rules are ignored when the user perceives there to be a special situation. This flaw was picked up by digital clocks, which also show 12-hour cycles, with a small LED indicator to indicate that it is AM or PM (with some clocks, "on" means PM and "off" means AM, and with others it is the opposite). Many mistakes happen only once and are not repeated - so by the time they are discovered one cannot observe how they came to be, and everything appears to be running smoothly (because it is running smoothly, and was even running smoothly when the mistake occurred). Slips - Occur when the user performs the right action badly, Mistakes - Occur when the user fails to perform the right action. The Psychology of Everyday Actions. "I think the first button does what I want" is what the user "tells" the machine by pressing the button.). Access a free summary of The Design of Everyday Things, by Donald A. Norman and 20,000 other business, leadership and nonfiction books on getAbstract. A task that is designed to require a user's constant attention is virtually guaranteed to fail if there is an interruption. The author also mentions laziness and procrastination as the cause of problems. A capture slip occurs when a person has done one repetitive activity and then switches to another that has a nearly-identical action sequence. The GPS system, stereo, climate control, or any other feature cannot be designed to distract the driver from driving.). A slip occurs when the user intended to do the right thing, which can be further categorized: A mistake occurs when a person fails to take the proper action, for which the author provides three bases: Where it is unclear whether an error is to be considered a slip or a mistake, it helps to consider that mistakes occur when planning to do something, whereas slips occur during the process of taking action. The checklist also casts every task into a sequence with a single thread of execution. The user is required to remember exactly where they were in the process of the task and what they needed to do next. This presumes that the design was correct, and that conditions will not change. Memory Slips. As such, the design of warning signals is a very complex and delicate matter. There is much to be learned in the wake of an accident, where things did not go as expected - knowing what went wrong is necessary to preventing similar accidents in future. The author tells an anecdote of a family trip in which they took a wrong turn and ended up on a highway that went to Las Vegas rather than to their destination. Worse still, they may be rewarded or see someone else rewarded for behavior that accomplished results by breaking rules. This often leads to problems in troubleshooting, particularly when there is different ownership of the "slices." Consider that near many sinks, the light switch and garbage disposal switch look the same and are placed side-by-side - resulting in disaster when someone wants to switch on the light to better see something that accidentally slipped into the drain. (EN: While this is a fact, I would dispute that the designer should, or even can, develop a device to accommodate this - as it's likely not possible to predict the unusual ways in which someone might try to hack a device.). This can also be practiced in real life. Unfortunately, not all errors are easy to detect. As soon as we find a human being to blame it on, the analysis stops. Rather than expecting users to remember procedures for unusual (emergency) procedures, provide them as-needed. Does it matter whether I forgot five minutes or five seconds before I should have done something? Young children are constantly attempting to do things that they are not tall or strong enough to do, in spite of warnings. The author finds this to be an increasing problem as electronics proliferate and designers want to provide the "convenience" of a single controller for many things, to imbue one device with multiple functions, or to create a wider array of settings for a single device. But it is nonetheless an effective technique for getting to the root cause of a problem - in spite of the fact that it falters when there are multiple factors that contribute. HOME > STUDIES > READING NOTES > Design of Everyday Things > Chapter 2. The potential is a great deal more concerning when there's much at stake: if landing a plane or performing a surgery is automated, such that pilots and doctors forget how to do these tasks, what happens when the machine breaks down? The author mentions the "Swiss cheese" model of accident causation, which suggests that each layer of security or prevention, like holes in a slice of cheese - and where the holes align, there is the opportunity for an accident to occur. His long and rambling consideration of this boils down to a few key points: In general, a person who has the knowledge and skill to perform a task, who takes adequate time and gives adequate attention, and who follows established procedures for working safely and efficiently, is highly unlikely to be the cause of an error. Confirming too often essentially undermines the value of a confirmation. A machine that only provides information about the present status does not do enough - particularly because the indication of status tends to be rather vague: "running" or "waiting" does not indicate what has been done and what remains to do. Insofar as design is concerned, this points to a weakness in planning contingencies. An "undo" function is very powerful and helpful in enabling users to back out of errors (or even confusing situations) and restore a device to its previous or original setting. The wrong action is performed - the user accidentally pulled the wrong lever, or their hand slid off of the right one such that it was not pulled properly. In attempting to classify things that can validly be ascribed to human error, the author found there to be two categories that cover the vast majority: slips and mistakes. Or it is not in the interest of the provider - like letting a user easily "undo" ordering a product. An interesting observation is that experienced people tend to slip more often than novices. Human-centered design (HCD) It means starting with a good understanding of people and the needs that the design … When a user who is willing to accept blame is in a conflict with an engineer who's unwilling to accept it, the result is obvious. In some instances, resiliency requires the product to be altered - a roof is built to withstand hurricane winds up to a certain force and has that property even when there is not a storm. (EN: It doesn't help that limits are set too low. First, errors can be detected only if there is feedback, and the more immediate the feedback, the more quickly the error can be detected. There are many instances in which equipment is running for longer and faster than is safe, or when employees cut corners because safety regulations make it impossible to work as quickly as management demands. The clock is a very old example of a device whose modality is poorly considered because the same 12-hour dial is used for both AM and PM settings - so the user must know (from some other source) if it is before or after noon to know which "mode" the clock is in. The problems with modes of operation are such that the author declares that any mode error "is really a design error." This chapter of The Design of Everyday Things introduces and formalizes basic concepts and principles of design from observations of everyday objects. The author suggests that this is part of the reason airplane cockpits are so difficult to learn - every item looks significantly different than others that are similar. In the lab, users are in a quiet environment, no distractions, no time pressures, holding a cell phone in both hands while sitting comfortably. And it attempts to do all of this with four small buttons that must be pressed in various combinations in order to access these functions. When asked what went wrong, they are at a loss to describe exactly what went wrong. A major source of errors is interruption - a person who was in the process of doing something is distracted for a time by something else and forgets where he left off. Organizations are just as bad as people in this regard: they fear litigation or a diminishment of their esteem if they admit to making an error. Action Slips. The author mentions SCUBA divers, specifically, who wear a combination of weights and air bladders to maintain they buoyancy in deep water. Observing and collecting information about the occurrence of errors is critical to improving the design. It's simply an unreasonable expectation. Also, computer programs will often hide or disable controls that are not necessary to the present step of a task. Workers soon learn that if they didn't bend or break the rules, they would get very little done. Chapter 1: The Psychopathology of Everyday Things. Typically, a more familiar or recently-performed sequence will replace a new or less familiar one. That seems like a good idea because "the printer is out of toner" is certainly more informative than a flashing yellow light. The book was published in multiple languages including English, consists of 240 pages and is available in Paperback format. The Design of Everyday Things: 1988-2038. Particularly in commercial scenarios, people are pressured to do as much as possible as fast as possible, as well as to press forward and get things done even when it is clear that doing so will compromise the quality of the outcome and even endanger the people involved. Consider that the reason students often cheat on school examinations comes from pressure to make good grades. In the case of a bank account, there is likely a failsafe that would prevent the transaction from going through because there are insufficient funds. The author refers to an annoying investigative technique called the "five whys" - which encourages investigators to ask "why" five times once a reason is found. Learn vocabulary, terms, and more with flashcards, games, and other study tools. A watch may function as a clock, a stopwatch, and a time; it may tell the time in multiple zones; it may enable the user to set multiple alarms. The items don't necessarily need to be identical to be mistaken for one another at a glance. Sherry Lin. The fact that they were able to take a curve rated for 30 mph at 35 emboldens them to ignore warnings and try going even faster next time, as well as to ignore warning signs on other curves given that the posted warning was wrong. Usability test. And very often, when the front line workers point out the danger to their superiors, they are threatened into following orders. Additionally, there is pressure in many workplaces to avoid or diminish errors, which increases the incentive to deny or cover up. The author's only advice is to be careful and invest time in doing proper analysis. He probably remembers what he was trying to do (though he may forget it entirely) but does not know how far along he was in the task and where he left off. There was no apparent mechanical cause for the problem, and it was ascribed to "pilot error" in that the pilots were shown to have made a variety of mistakes in different incidents. All that a flashing yellow light does is cause the user to experience anxiety and feel helpless. For that reason, senior people are often fond of checklists, as it enhances their sense of authority and control over others to compel their peers and subordinates to follow a checklist they provided, and which they often ignore in their own work. The Design of Everyday Things - Chapter 1 In chapter one of Donald A. Norman's book The Design of Everyday Things, I found myself very surprised. Norman, D. A. In many instances workers are slowed down to accommodate those who wish to monitor and control their work - such that paperwork takes longer than the task itself. ), Another constraint put in place by some systems is the requirement to confirm an action before it is undertaken, particularly when it will result in an action that is not easily undone (deleting a file, placing an order, etc.). The error is not solved, and more errors may now be made as a result of acting on a bad diagnosis. Ultimately, it means that the designer must take responsibility for designing a device that will be used by a person - and ensure that the man-machine system has the best chances of success. If everything makes the same (or similar) sound to issue a warning, there is a period of uncertainty as to what needs attention. "Bad design cannot be patched up with labels, instructions manuals, or training courses." September 6, 2014 [notes] The Design of Everyday Things The Design of Everyday Things (2002) by Donald A. Norman #. And where a machine fails because of a broken part (clearly a mechanical defect), we then say it is someone's fault for not inspecting and maintaining the machine properly. The first edition of the novel was published in 1988, and was written by Donald A. Norman. The root cause is something that sets in motion a chain of events that leads to a disaster, such that we believe that if truth one thing did not happen then the disaster would not have happened. An ATM receiving such a request would do well to raise an eyebrow, digitally speaking, and ask if the amount is correct. (EN: I have a sense this is done to avoid culpability - when things go wrong the rule-maker escapes blame by placing responsibility on the rule-follower.). The moral to the story is that people generally assume that they have done the right thing and are proceeding on track to the right destination - and when confronted with signs that they are headed in the wrong direction, they assume the signs are wrong and continue on their merry way. Airport security personnel practice certain procedures daily which are meant to prevent hijackings, but have enhanced procedures when they believe the risk to be higher than usual. Rather than assuming people will understand the rules, test whether they can do a task following your instructions. The Design of Everyday Things. It requires people to change their attitudes - because they will alter their devices and ignore their training if they feel pressured to do or refrain from doing something. The problem can be made worse, still, if the device automatically changes modes sometimes. They undertake routine tasks with very little or no thought or conscious attention - which means inattentiveness, is the very thing that causes experts to make mistakes. Safety procedures for the pyrotechnics were followed to the letter (the procedures did not account for the low ceiling and acoustic tiles), exits were locked (standard procedure to keep people from leaving without paying their tabs), and the staff followed procedures that did not account for an emergency situation. The problem is that "something bad happened" is completely insufficient. People run out of gas because they do not feel they have the time to stop when the gauge is getting low, or notice it but think they can put it off. You must plan for contingencies. There's no reminder of what the goal was, what was already done, and what the next step happens to be. And given that users may have multiple windows open, that they are closed by an action that can be accidental, etc. There is a Japanese term "pokayoke" which refers to measures taken to prevent errors from occurring, and also refers to the device used to do so. A bad system enables and even encourages users to do things that create errors - or provides no clear indication of what is expected of the user, or which places too much burden on the user to know or learn. If an error can be discovered quickly, it can be rectified to avoid or minimize harm. "I have three buttons. SUMMARY: The Design of Everyday Things: Revised Edition | Chapter-by-Chapter Review and Summation - NOT ORIGINAL BOOK The Design of Everyday Things is a powerful primer on how—and why—some products satisfy customers while others only frustrate them. Unfortunately, this is not true. Knowledge-based behavior takes place in novel situations, when an individual must discover a solution to a problem he has never before encountered by applying his knowledge of similar situations and general principles of action. Chapter 1: The Psychopathology of Everyday Things. Divers are supposed to drop their weights before they emerge from the water, but many do not because the weights are costly to replace. Engineers want to control the people who use their devices, controlling and directing their every action as if they were part of the machine. "Undoing" is not always possible - particularly with devices that take actions in the physical world (you cannot "undo" burnt toast) - and there are situations in which you may not wish the user to undo their action (if it was right), but it's a good idea in principle. Consider proximity in more dimensions than physical space when designing to avoid similarity slips: proximity in time (one thing is done shortly after another), proximity in function (they do things that are similar), etc. Did the user do something wrong or did the device misguide him? It wasn't discovered until years later that that pilots were suffering hypoxia because they were not getting enough oxygen through the plane's ventilation system and were becoming incapacitated. Summary… One of the most common problems with these clocks is being unable to set it correctly - you meant to set an alarm for seven in the morning and it goes off at seven at night instead. However, this is not entirely true: a machine was built by a human being to be used by other human beings. One significant problem is that engineers are simply looking to scapegoat human beings for flaws in their design. When a medical technician overdoses a patient with an infusion pump, the manufacturer of the pump does not escape liability for the technician's inability to understand the awkward and haphazard design of their device. In the workplace, rules and procedures often become far more convoluted than necessary. SUMMARY: The Design of Everyday Things: Revised Edition | Chapter-by-Chapter Review and Summation - NOT ORIGINAL BOOK The Design of Everyday Things is a powerful primer on how—and why—some products satisfy customers while others only frustrate them. People insist on performing activities when they are physically unable to do so. Created by. For example, you can safely vacuum the living room floor while waiting for the washing machine to run - but you should not try to vacuum the floor while waiting for the stove to heat oil to frying temperature. This does not match the situation of a worker who will perform the task unsupervised, during a shift lasting 8 or 12 hours, while being distracted by other tasks and things in his environment, and is under pressure to perform. The user's natural habitat - which is to say, in situations where a device is going to be used - is not a quiet testing lab in which there are no distractions and no stress. When tasks can be done in any order, or even at the same time, the checklist forces them into an unnecessary order. In the real world, the application is used by a person while standing, holding the device in one hand, in a noisy environment, and distracted/interrupted because they were waiting for something else to happen. He mentions the control board of a nuclear power plant, the cockpit of an airplane, or a surgical theater where there are many devices. A memory-based mistake is similar to a memory slip - but instead of failing to do the right thing, the person takes a wrong action believing it to be right. But the author feels that this is terribly wrong. This becomes problematic when the situation is not adequately analyzed to recognize a difference. It should be no trouble at all to save a file when a window is closed and keep a list of recently-deleted items that can be restored. Consider an assembly line operation in which a batch of screws is not properly threaded. Milkr works in line with your … It's likely useful to point out that "it is possible, but we don't want them to do it" to clarify requirements. He mentions verbal slips - which are routinely experienced when people are attempting to speak too rapidly, or utter a phrase that requires a bit of lingual acrobatics, and end up saying the wrong word or even garbling a phrase. All decisions are made based on human judgment, and judgment has been divided into three modes: skill-based, rule-based, and knowledge-based. Lim Zhiyang. There is some indication that those who build machines should take responsibility, largely in consumer lawsuits. A person has decided on an inappropriate course of action, believing it is what must be done to accomplish the goal. This is the basis of phobias: a person who was once bitten by a dog believes that all dogs are going to bite him, or at least assess the risk that any given dog will bite to be greater. London: MIT Press (UK edition) What has changed from the earlier book? HOME > STUDIES > READING NOTES > Design of Everyday Things > Chapter 6 6 - Design Thinking In consulting, the author makes a "rule" of never solving the problem the client presents, because the client's attitude tends to be one of "make the user accommodate my product" rather than coaching the client to make a product that is usable. Why some objects, as simple as doors, please their users while others frustrate them. The author mentions that checklists have been highly successful in aviation - such that all flights use a "pre-flight checklist" that is run through by pilot and copilot before taking off. The author regurgitates some of the previous material on mistakes and slips: whether the user chose to do the wrong thing or tried to do the right thing but failed in the process. Other mistakes are difficult to observe because they are not systematic. There are fewer failures, but those that occur tend to be rather huge. It is presumed that the user is a person of little experience or intelligence and must be told what to do - and that the individual or group that defines rules is capable of clearly communicating the correct action in a given situation. There may have been several things that could have been done differently to avoid the accident - and there may be several things that need to be corrected to avoid it from happening again. For example, I have encountered similar glass swinging doors that Norman told about. Fortunately, automation is very poor at replacing knowledge workers for complex tasks, and is generally leveraged for doing menial work - in much the same way as "cruise control" in an automobile relieves the driver of a need to keep pressure on the gas pedal, but does not take over steering the car, and a human driver can easily disable it and take control. Those who formulate rules will include phrases such as "when necessary" and assume that users will know when it is necessary to take the prescribed action. Confirmations are valuable when there is the possibility of making a mistake. The problem is that multi-tasking isn't actually doing two things at once, but switching attention from one thing to another: you start to do task A, then switch to task B, then go back to A, then go back to B, etc. Particularly when the user is an employee of a company, he is likely under tremendous pressure to meet performance goals, and if he succeeds at meeting those goals this year they will be set more aggressively in the following year, to the point at which catastrophes become inevitable. As a result, people don't read instructions. Another drawback to automation is that people place such faith in its perfection that there are often no plans for what to do in the case of failure. A simple task becomes very complex when the user is made to behave in an unusual or seemingly unnecessary manner to avoid an accident that occurs only in rare situations. Done, and other study tools to raise an eyebrow, digitally speaking, and errors. 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