The author previously mentioned constraints that prevent the user from doing the wrong thing - such as making one prong of an electric plug (and socket) slightly larger so that it cannot be plugged in backwards. Consider that when people hear a sound like a pistol shot, the first thing they think is that it is likely a car's exhaust backfiring. Why did the pilot fail to initiate the recovery procedure? The Design of Everyday Things (216) Design, therefore, takes on political significance. A mode error occurs when a device has different states of operation and the user does not observe (or makes an assumption) about the mode in which the device is presently set. As designers, we should recognize that panic is the cause of bad decisions, and exercise patience. 5,6,7 Chapter 5: To Err Is Human So far, I like this chapter the best because the slips are something that I, and a lot of other people, can relate to. I'd agree that this is stupid and arrogant humans, but devices should consider whether their lag time encourages this behavior and what might be done to prevent disaster if the person fails to return soon enough.). It's not at all a realistic test.). Still, some people are not convinced and believe that they are capable of multitasking well. It's most common in computer software, but even consumer electronics such as television sets have a "back" button in case the user accidentally changed the channel. Personal computers were not widespread, the Internet did not exist for most of the world, and the smart phone was unheard of. People who perform a task often also become "skilled" - which means they can do the task without conscious effort, and the ability to do so is linked to a high level of efficiency and ease when a person can "effortlessly" perform a task. Because it went into an uncontrolled dive. And so on. The person reading the checklist gives the list his entire focus and will question the logic of deviating from the instructions, such that the other person must consider their behavior more carefully. Part 2 — The Design of Everyday Things (Revised & Expanded Edition) — Book Summary & Key Points. It doesn't tell the user what went wrong, how they can continue with what they wanted to do, or how to avoid making the same mistake in future. 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. This is the reason the many activities and professions require government licensing - accountants and doctors must be licensed, as must airplane pilots and automobile drivers. The preface explains why the book was revised and then, chapter by chapter, what has changed. For example, if taking an inventory of items that are packaged in pairs (counting 2-4-6-8-10) and then switching to items packaged in sets of three (count 3-6-9-12-15) it would not be entirely unpredictable for a him to blend the two (3-6-8-10-12) and bungle the count. However, much of the conversation is nonverbal. He mentions an instance in which mode-error slippage became deadly: one of the models of Airbus airplane had an instrument that assisted pilots in landing the plane (or in this instance, assisted them in crashing it) - a single display enabled the operator to enter the degree of descent or the decrease in speed, in two different modes. Social pressure is an important factor that has a very strong influence on everyday behavior. The outcome is tragic when everyone things the same thing - assuming that someone else will catch their errors - and nobody is being particularly attentive to their work. And worse, the pressure to meet quotas and goals compels them to ignore the rules - they will be punished either way. Unfortunately, people do not, and in some instances cannot, give their undivided attention to a device. 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. This often leads to problems in troubleshooting, particularly when there is different ownership of the "slices." Interruptions and multitasking can be disastrous in critical moments. First, errors can be detected only if there is feedback, and the more immediate the feedback, the more quickly the error can be detected. (EN: It's worth noting that knowledge is the basis of all action. .. Optics usually describes the behaviour of visible, ultraviolet, and infrared light. The goal: guide the user effortlessly to the right action on the right control at the right time. However, this is not entirely true: a machine was built by a human being to be used by other human beings. Simply stated, similarity of actions should be considered when designing a task or device. A device may do many things, and users need to know only one or two, Consider the goal. Spell. The author mentions that few actions should require confirmation - or better still, make more actions reversible. But remove the confirmation, and users will be upset that you didn't warn them that their action would have consequences. Consider that the reason students often cheat on school examinations comes from pressure to make good grades. One suggested approach is to consider what might happen if a person were to walk away from the task, and ask someone else to "finish this for me" - can the person who stepped in to help out see what needs to be done? I am so bad at mechanical things." As has been stated, it is not at all reasonable for an engineer to expect that the user will give complete and constant vigilance to his device. Putting your car in gear without disengaging the parking brake, Being unable to find something that's in its usual place, Neglecting to put something back in its usual place after using it, Forgetting why you entered a room as soon as you've walked in, Interruption - a person is interrupted in the middle of a task and loses his place, Complexity - a task involves so many intricate steps that a person can't remember them all, Delay - there is time between planning a task and undertaking it. PLAY. For example, a memory lapse error occurs when something that should have happened did not happen. The author also mentions the age-old concern that automation makes people dumber. However, if that were taken to an extreme of warning whenever a window is closed, the user would constantly be "confirming" the close of every window, and would become trained to simply click "OK" without paying attention. In this culture, people are punished for failing to report errors rather than for making them. The author speaks of a nightclub fire that killed over 200 people in Brazil. Flashcards. Most everyday errors are slips, in which a person means to do one thing but finds themselves doing another. There is also the irrational belief that things will work themselves out. We cannot fix problems unless we are aware they exist - and we cannot be aware that they exist until people report them. Chapter 1 Summary. 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. The idiotic practice of "let's say 30 knowing that people will drive 40 anyway" is self-defeating.). Learn vocabulary, terms, and more with flashcards, games, and other study tools. He briefly mentions the self-reinforcing nature of stupidity. Consider the case of speeding: people will drive faster than the posted limit when they do not believe that the limit is reasonable. When this happens, the rules may be incomprehensible, or they will be forgotten, or they will simply be ignored. Frederick Taylor's principles of scientific management are largely based on observing the strength, speed, and stamina of human workers in industrial jobs and designing tasks to suit their capacities. The author suggests that the more people will check and inspect work after it is done, the less attentive a worker will be because he does not bear responsibility for the outcome. Various attempts by designers to overcome the inherent problems of modes have not been successful in making a bad idea work. It may be for fear of disappointing parents, or because they have been told that grades are critical to their future, or merely because they wish to avoid ridicule or ostracism from peers for making poor grades. He mentions discussion with people who, in a relaxed mood, plainly admit that they make stupid mistakes, like forgetting to turn the stove off, nodding off at their desks, and not paying attention - but these same people are highly critical of other people for making "human errors" for not being fully alert and attentive at all times. 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. Another problem with root-cause analysis is that it presumes only one thing is to blame for an accident, when in reality many things may have gone wrong. He explained some core principles that can be followed to make more human-centered designed products. There's no reminder of what the goal was, what was already done, and what the next step happens to be. 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. Slips - Occur when the user performs the right action badly, Mistakes - Occur when the user fails to perform the right action. (2013). Cross-checks can also be helpful. People also tend to want to discover innovative ways to do things - finding new or more efficient ways to use a device by ignoring the intentions of the designer. Does it matter whether I forgot five minutes or five seconds before I should have done something?) Simplify the task. The world is full of things that will distract a person from a task, or cause them to turn away "just for a moment" from a running machine without switching it off. While machines and computers are very good at responding consistently to commands, they often require the human user to learn to speak their language or to perform an action that feels unnatural or awkward in order to get the device to do what was wanted. If the user failed to press a button to release excess pressure, then it's the person's faulty - even if the machine provided no gauge or indicator to tell him that the pressure was dangerously high. Better, use illustrations rather than words. Usability test. There are several areas of design specialty: It's a good idea that can be helpful in many instances, but a test is never as complex, stressful, or unpredictable as a real disaster - so no recovery plan should be regarded as perfect or foolproof. They believe that they can adjust the efficiency or effectiveness of the outcome by doing things differently - whether this means they want to do things better, or are willing to accept a less-than-perfect outcome for the sake of efficiency and expediency. Divers are supposed to drop their weights before they emerge from the water, but many do not because the weights are costly to replace. When considering automation, keep in mind the unique capabilities of man as well as machine. Faulty diagnoses compound the problem of unobserved mistakes. You must use constraints to prevent mistakes. But the author feels that this is terribly wrong. Where the rule is written in convoluted language, often to provide specificity, it becomes so complicated that users cannot possibly understand what it actually means. Other mistakes are difficult to observe because they are not systematic. They do not wish to consider an option that makes them feel unsafe. Use short sentences and small words to make rules easy to follow. You must plan for contingencies. 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. There is some indication that those who build machines should take responsibility, largely in consumer lawsuits. "The clutter" is a lot of accounts of Airbus crashes due to problems with instrumentation and controls - particularly of the 300-model plan that introduced a lot of technical sophistication to the cockpit.). There are fewer failures, but those that occur tend to be rather huge. To roll through a red light because it's 2 am and there are no other cars on the road, or to speed because they are late for an appointment. But even in that case, a warning before doing something foolish is better (psychologically) than an error message afterward. 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 is not entirely related to the workplace, as it happens in other situations. Unfortunately, not all errors are easy to detect. You must decide when the user's attention should be called (and not too often), create a stimulus that is adequately intense to attract attention (but not too intense), enable the user to recognize what has gone wrong, and inform the user of what must be done to continue. And he means this quite literally. The author mentions the attitude called "jidoka" promoted within the Toyota Motor Corporation, which encourages workers to pull a cord to stop the assembly line when they notice something is wrong. In this instance, it is because it could be disastrous if two things looked the same (if the switch to raise the landing gear looks like the switch to lower the wing flaps, pilots might mistake one for the other). Another common problem with warnings, particularly audio ones, is that they are not sufficiently unique. They falsify log files so that they can drive more hours per day than the law allows (for the sake of ensuring they get enough rest to be alert on the road) and disable or circumvent devices that control their speed (for the sake of ensuring they can make a delivery on time when schedules are inflexible). In the workplace, rules and procedures often become far more convoluted than necessary. Day 5994. If an error can be discovered quickly, it can be rectified to avoid or minimize harm. Both assumptions are often wrong. 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. Some constraints are merely to make it more difficult to do something incorrect. People insist on using a trial-and-error approach and figuring things out when they don't understand and haven't adequate competence. ), (EN: Another thing that the author fails to mention is that processing time encourages people to multitask. 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. 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. And in that sense, the human who made the error was not the operator of a device, but its designer. 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. 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. The author speaks of disaster planning, which simulates and emergency situation to test that people remember to follow emergency procedures. The author notes that this blends the various techniques he discusses in this book, as some pokayoke are labels, other constraints, and still others are reminders. He mentions that having two-person teams work a checklist and instructions is often more effective: one person reads the instructions and another performs the actions. Much of conversation is error-handling: we misinterpret things and have to be brought back on track, or need to correct what we've said to keep the other person on track, or find something that they say to be questionable and debate - and this is all still necessary even when we have made no grammatical errors (which are often irrelevant because we listen for meaning and often do not notice minor mistakes in speech). (EN: There have been a number of psychological experiments in this area which come to the same conclusion - that it is more efficient and effective to do A from start to finish and then to address task B rather than an ABABABAAB kind of pattern. … The notion that there is only one possible cause of an accident (or the tendency to stop investigating when one cause is found) gives rise to erroneous thinking ... "if only" one thing had happened differently, the accident would not have occurred. The main characters of this design, non fiction story are , . The reason for this is that novices tend to pay closer attention to the task they are doing, whereas skilled people often perform tasks in a more automatic/unconscious manner and may fail to pay sufficient attention to what they are doing. Vagueness is a particular problem for rules-based procedures. Those who own slice A suggest it was the responsibility of slice B to prevent an error that got past them, and those who own slice B blame slice A for letting it get through to their layer in the first place. 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: Hugo Munsterberg raised the very same point shortly after Taylor, but his work garnered little attention. 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. Because the pilot failed to initiate a recovery procedure. (EN: The distinction seems a bit dodgy to me. The knowledge in the world and in the head. As the name implies, "root cause" analysis seeks to identify a single cause for an accident. 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. Consider the primary use. Chapter 1: Psychopathology Of Everyday Things. 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. So how can we facilitate error detection? But the truth is, sometimes people really are at fault. As a result, there may be a number of rules-based mistakes: Another mistake commonly made by rules-makers is assuming that everything will be normal. but there are also instances in which a machine can be designed to remind a person of something they neglected to do (the chime that sounds if a car is starting and the seat belt is not fastened) or to avoid common lapses (an ATM that allows the user to swipe his card rather than insert it). They attempt to figure things out, and will not look to the documentation until something has already gone wrong. He mentions that Sigmund Freud made much ado about such verbal slips - probably too much ado. Critical to making devices more intelligent is in making them conversational - giving them the ability to interpret what users want, and to communicate and react to them with some consideration of the way in which they are naturally inclined to act, including the possibility they may be inclined to do things when they wish to achieve that goal. In general, violations are a valid form of human error - but it must always be questioned whether the "rules" are communicated clearly and are sensible and reasonable. HOME > STUDIES > READING NOTES > Design of Everyday Things > Chapter 2. Checklist design, meanwhile, is extremely difficult to do well: the designer of a checklist must be able to envision a task (one which he may never have performed) and account for all possibilities and contingencies in creating a comprehensive list that is at the same time not burdensome or inefficient. The Psychology of Everyday Actions. 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. 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. He has to see several malfunctions before he will accept that there is something wrong with the equipment and what he witnessed was not merely a temporary glitch in the system. 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. It seems like the only time that engineers are willing to accept the blame for the failure of their devices is when an incident occurs when an item was untouched by human hands. Chapter 1: The Psychopathology of Everyday Things. People are flexible, versatile, and creative - and machines cannot replace these qualities. They are expected to make their devices understandable and to provide warnings and failsafe measures should someone decide to do the wrong thing. The author muses on the topic of checklists, which he feels to be powerful tools in guiding users because the presence of a checklist enables them to remember the steps in a task and the items in the list provide the opportunity to provide details and instructions. Each relies on the assumption that taking action X will have result Y - based on experience (skill), procedure (rules), or extemporaneous reasoning (knowledge) - but an action will produce a result only under certain conditions, and all three approaches anticipate that the conditions will be "normal," hence failure occurs when the conditions are not as they are assumed. The author has observed that most people stop investigating once they have found someone (a person) to blame - and that in most instances, it is fear of punishment that causes them to seek someone else to lay the blame upon. They are afraid that if they accept the blame for an error, there may be fired or sued or punished in some other way. That seems like a good idea because "the printer is out of toner" is certainly more informative than a flashing yellow light. Design of Everyday Things - Ch. The Design of Everyday Things. (2013). 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. (EN: Hugo Munsterberg raised the very same point shortly after Taylor, but his work garnered little attention.). Or it is not in the interest of the provider - like letting a user easily "undo" ordering a product. If they have to wait five minutes for the device to do something, that's five minutes they can spend doing something else. People are creative and exploratory beings, who enjoy figuring things out (so long as we are successful at doing so) and dislike being told what to do. In such instances, consistency works against itself and a stronger visual distinction must be made when there is a potential for error. 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. It takes a dramatic indication for them to accept, or even to consider, that they have done something wrong. So this is tantamount to stating that the people who build machines are not intelligent enough to understand the people who use them - and so users must adapt to compensate for the incompetence of the builder. The author refers to a psychological study (Fischoff) which contrasted two groups of participants: This is a natural response, as we count on experience of the past to guide us in predicting what we should expect of the future, but it has a number of drawbacks - chiefly, that we expect the future to be like the past, even if the past was abnormal. 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). 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. , keep in mind the unique capabilities of human beings decades ago takes a dramatic indication for them to the. More obvious to me are perpetuated of an action is not properly threaded it more difficult to.... 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