This book is a great reference for the complex psychological concepts behind the fundamentals of designing intuitive products and experiences.
Users spend most of their time on other sites, and they prefer your site to work the same way as all the other sites they already know.
Dates back to Jakob Nielsen's works in 2000. The less mental energy users have to spend learning an interface, the more they can dedicate to achieve their objectives.
A mental model is what we thing we know about a system, especially how it works. We also tend to apply the knowledge when interacting with similar types of systems.
Using personas would help us to frame design decisions based on the needs of the real audience.
This law might sound like it's enforcing all the websites look the same, which is a completely valid concern. However, we should keep in mind the form should follow function in order to deliver usable stuff. There's always room for innovation.
Always being with common patterns and conventions, and only depart from them when it makes sense to. If you can make a compelling argument for making something different to improve the core user experience, that's a good sign that it's worth exploring.
The time to acquire a target is a function of the distance to and size of the target.
The time it takes to make a decision increases with the number and complexity of choices available.
The amount of resources needed to understand and interact with an interface is known as cognitive load.
Can be used to determine which elements are vital for the interface to achieve the expected task
Removing text labels and just leaving icons in order to simplify the interface (iOS bottom tab bar, Facebook example) may lead to confusion for some users.
The average person can keep only 7 (+-2) items in their working memory.
Cognitive psychologist George Miller's 1956 paper titled "The Magical Number Seven, Plus or Minus Two: Some Limits on Our Capacity for Processing Information". The research was just indicating the best performing item count in a chuck was around that number, however the conclusion of the research under-interpreted as The Magical Number Seven!, which was a rhetorical choice of words from the beginning.
Miller found the size of the chunks (either letters or words) did not seem to matter, but the number of the items in chunks and the number of chunks did.
Phone number input formatting: 4408675309 —> (440) 867-5309
Do not try to apply Miller's Law to components that don't need to be memorized by the user, such as navigation menus.
Be conservative in what you do, be liberal in what you accept from others.
Also known as the robustness principle, based on the idea of a significant contributor of the TCP: John Postel. It's a guideline for the systems to follow while receiving and sending messages to the network they are in. The way web browsers parse and render HTML and CSS is also similar, they handle the syntax errors gracefully.
Postel's law comes with an opportunity to improve the accessibility, but it may also have some downsides like adjustable font sizes breaking the UI, translations in other languages breaks the positioning and etc.
People judge an experience largely based on how they feld at its peak and at its end, rather than on the total sum or average of every moment of the experience.
Various control groups found the less painful (even though they are more long) experiences more pleasant. Colonoscopy and water temperature experiments.
Can be used to map out the user journey and pinpoint the peak and end steps.
It is inevitable that something go wrong at some point in the lifespan of the journey. However, handling those errors gracefully and communicating them with the user in a sympathetic way (cute 404 messages) may decrease the negative impact.
Users often perceive aesthetically pleasing design as more usable.
Goes back to the user testing sessions done for the ATM interfaces in Japan.
Contrary to what we have been taught not to do, people do in fact judge the books by their covers.
As discussed in the book Thinking Fast and Slow by Daniel Kahneman, our brain has two systems. The first one is used more effortlessly which carries over the intrinsic inheritance and gains. It makes quick scans for the objects, or the other stuff that we are interacting with, to decide they are worthy or not. This also applies to digital products, or services.
System 2 is used for more advanced tasks which require computation. It operates more slowly and requires mental effort to examine situations. Focus, research, memory retrievals and mathematical operations are some examples.
Products that are both aesthetic and usable.
Braun SK4, designed by Hans Gugelot and Dieter Rams.
Apple's inspiration of the Braun products.
When multiple similar objects are present, the other one that differs from the rest is most likely to be remembered.
Dates back to the researches of German psychiatrist and pediatrician Hedwig von Restroff. It is a bit obvious: we best remember the distinctly different elements better.
Attention is a limited resource, and we don't always realize the changes in front of us, unless they create a sense of attention.
Banner blindness: users think the content is an ad.
Change blindness: users don't realize the changes.
While designing for attention, we need to make sure the approaches taken won't create a noise in the interface, and they are accessible for people with disabilities.
For any system, there is a certain amount of complexity that cannot be reduced.
Dates back to the Xerox PARC days around mid-1980s. Lerry Tesler was a computer scientist working on the project, and his observed that the way users interact with a system is just as important as the system itself.
When an interface has been simplified to the point of abstraction, there is no longer enough information available for the users to make informed decisions.
Again, ambiguous icons without text labels. We still don't have a standardized mapping for the icons and actions. Presenting them without labels may lead to an abstraction.
Productivity soars when a computer and its users interact at a pace (<400ms) that ensures that neither has to wait on the other.
IBM paper published in 1982 states the productivity increases in a direct correlation with the response time.
Fast response times can also cause several issues such as
Purposefully adding a delay to process can actually increase its perceived value and instill a sense of trust, even when the process actually takes much less time.
Facebook's Security Checkup process takes actually less time, but they prolong it to educate user.
Our responsibilities as designers, humane design, Skinner's Box...
Use more meaningful metrics like helping people to achieve their goals rather than "daily active users" or "time spent on site".
Placing the edge cases in our thinking would help us to ensure that we're creating more resilient products that considers the most vulnerable cases by default.
Quantitative data tells us lots of useful things but emotions. It's critical to gather other metrics by communicating with the users in order to understand them better, and serve them better.
Obviously, designers who learn and master psychological principles would produce more anticipating products and services for the humanity. This section goes through how to increase awareness over the concepts discussed in this book, and how to internalize them to use in our works.
The most effective way to leverage psychology in the design process is to embed it into everyday decision making.
By visibility: print-out the posters of each concept and put them into walls.
Show and tell: knowledge sharing sessions on new techniques, tools and findings over the recent events such as usability tests or a recently completed project.
Teams can create a consistent decision making within the design process by establishing a set of guidelines that represent the priorities and goals of a design team and serve as a foundation. Those principles would be used as the north star as the team produces more and more.
Define the principle, connect it with one or more laws, set rules to support them which should be used by all the members while designing interfaces.
Principle: Clarity over abundance of choice.
Description: According to Hick's Law, we know that the time it takes to make a decision increases with the number and complexity of choices available.
Rules — To achieve this goal, we must:
Familiarity over novelty
According to Jacob's Law, we know that the users spend most of their time on other sides, and they prefer our site to work the same away as all the other sites they already know.
To achieve this goal, we must: