This is my summary and notes from The Design of Everyday Things by Don Norman. Please use the link if you decide to buy the book after reading this as it contains my affiliate code. Thanks.
We have to accept human behavior the way it is, not the way we would wish it to be.
The paradox of technology and the challenge for a designer:
The same technology that simplified life by providing more functions in each device also complicates life by making the device harder to learn or use.
1* What do I want to accomplish?2* What are the alternative action sequences?3* What action can I do now?4* How do I do it?5* What happened?6* What does it mean?7* Is this okay? Have I accomplished my goal?
It is a profoundly erroneous truism, repeated by all copy-books and by eminent people when they are making speeches, that we should cultivate the habit of thinking of what we are doing. The precise opposite is the case. Civilization advances by extending the number of important operations which we can perform without thinking about them.
— Alfred North Whitehead, 1911.
Tradeoffs between knowledge in the world and in the head | Knowledge in the world | Knowledge in the head | |------------------------|-----------------------| | Information is readily and easily available whenever perceivable. | Material in working memory is readily available. Otherwise considerable search and effort may be required. | | Interpretation substitutes for learning. How easy it is to interpret knowledge in the world depends upon the skill of the designer. | Requires learning, which can be considerable. Learning is made easier if there is meaning or structure to the material or if there is a good conceptual model. | | Slowed by the need to find and interpret the knowledge. | Can be efficient, especially if so well-learned that it is automated | | Ease of use at first encounter is high | Ease of use at first encounter is low. | | Can be ugly and inelegant, especially if there is a need to maintain a lot of knowledge. This can lead to clutter. Here is where the skills of the graphics and industrial designer play major roles. | Nothing needs to be visible, which gives more freedom to the designer. This leads to a cleaner, more pleasing appearance—at the cost of ease of use at first encounter, learning, and remembering. |
The merits of the new system are irrelevant: it is the change that is upsetting.
Error occurs for many reasons. The most common is in the nature of the tasks and procedures that require people to behave in unnatural ways — staying alert for hours at a time, providing precise, accurate control specifications, all the while multitasking, doing several things at once, and subjected to multiple interfering activities. Interruptions are a common reason for errors, not helped by designs and procedures that assume full, dedicated attention yet that does not make it easy to resume operations after an interruption.
75-95% of industrial accidents are caused by human error.
Root cause analysis: investigate the accident until the single, underlying cause is found.
Most attempts to find the cause of an accident are flawed for 2 reasons:
When root cause analysis discovers a human error in the chain, its work has just begun: now we apply the analysis to understand why the error occurred, and what can be done to prevent it.
Treat all failures in the same way: find the fundamental causes and redesign the system so that these can no longer lead to problems.
Root cause analysis is intended to determine the underlying cause of an incident, not the proximate cause.
The Five Whys: Japanese procedure for getting at root causes (originally developed at Toyota). The goal is to keep moving the inquiry deeper even after a reason has been found: ask why that was the cause.
Deliberate violations: cases where people intentionally violate procedures and regulations. These happen for different reasons:
Although violations are a form of error, these are organizational and societal errors, important but outside the scope of the design of everyday things.
Human error is defined as any deviance from “appropriate” behavior.
Types of errors:
Checklists are powerful tools, proven to increase the accuracy of behavior and reduce error, particularly slips and memory lapses.
It’s bad design to impose a sequential structure to task execution unless the task itself requires it.
Design lessons from the study of errors:
Resilience engineering is a paradigm for safety management that focuses on how to help people cope with complexity under pressure to achieve success. It strongly contrasts with what is typical today — a paradigm of tabulating error as if it were a thing, followed by interventions to reduce this count. A resilient organization treats safety as a core value, not a commodity that can be counted. Indeed, safety shows itself only by the events that do not happen! Rather than view past success as a reason to ramp down investments, such organizations continue to invest in anticipating the changing potential for failure because they appreciate that their knowledge of the gaps is imperfect and that their environment constantly changes. One measure of resilience is therefore the ability to create foresight — to anticipate the changing shape of risk.
In theory, there is no difference between theory and practice. In practice, there is.
Plus ça change, plus c'est la même chose.
The more things change, the more they are the same.