Psychology is integrated into every step of the user experience (UX) design process. Understanding a few key principles of how people think can help you design digital products that work better for your users.
This article gives a primer on some basic psychology principles that every interaction designer should know. For each one, I’ve explained the principle and given a couple design rules of thumb (heuristics) we can take from it. Once you start noticing these design heuristics in digital products you use, you’ll be able to better understand why these products work so well.
Let’s dive in!
The Psychology Behind Good User Experience Design: Five Key Principles
If you’re interested in one principle in particular, simple select it from the list below to jump straight to it.
- Show users value before asking them to do anything
- Don’t bombard your users, guide them
- Don’t make users work
- Don’t do anything crazy
- Don’t ask your users to do your job
1. Show users value before asking them to do anything
People are skeptical about putting out effort, time, or money. You’re probably already familiar with the cost-benefit principle, which says that people weigh the potential value they get against what it’ll cost them. As a UX designer, it’s your job to foreground the benefit over the cost.
To do so, you can lean on a related psychological concept called reciprocation. This basically means people will trust you and be happier to put out effort for you if you do something for them. So your goal should always be to demonstrate the value of a product or a feature before requiring anything of users, not after.
Guest access: Let users explore your app or site before requiring them to login. Research has proven that login walls make people run screaming, so delay that Create Account prompt until you’ve got users convinced it’ll be worth it.
- Delay requests: Delay asking users to allow notifications, share their location, or give personal information until the moment when it’s needed. These requests shouldn’t be the first interaction your users have with your product.
If you give a little first, you’ll be rewarded with happier users.
2. Don’t bombard your users, guide them
Ever read overly detailed instructions and lose track of what’s what? Or get a headache filling out a form that’s too complex? You’re not alone. There’s a reason why less than 10% of Americans in this survey bother trying to interpret IRS forms to file their own taxes!
People can only use so much brain power at once; we have a limited cognitive load. As a designer, you can reduce users’ stress by taking this limited cognitive load into account.
Break things up: As a user, you’re probably already familiar with progressive disclosure, though you may not know the term. It just means splitting detailed information into bite sized chunks and revealing it only when it’s necessary. You can use this with onboarding, setting up a feed, or e-commerce check out.
- Create focal points: Design relies heavily on a set of psychological principles called Gestalt principles to guide users through pages and screens more easily. Get to know these principles and use them to help users navigate.
3. Don’t make users work
This one is super intuitive, but it’s also borne out by research. When people have to think or use effort, they get tired and grumpy. This probably resonates with you. In UX, anything that requires users to think or work is called an interaction cost, which is a nice term because it reminds us of that cost-benefit idea.
Perhaps even more interesting is research that shows that this type of interaction cost makes people worse at…well, almost everything. Ego depletion is a phenomenon where people evaluate information more poorly, have less self control, and just perform worse in many ways after having to expend mental or physical energy. Your job as a designer is to reduce interaction costs at all costs.
Use persistent labels: One easy way to reduce interaction cost is by reducing guesswork for users. Icons, key sections, and form fields should generally have labels that are always visible for the lowest interaction cost.
- Make it easy to input information: There’s never an advantage to making users choose their location from a drop down list of 130 countries. Think carefully about the UI controls you offer and choose the right controls for each piece of information.
4. Don’t do anything too crazy (AKA keep it familiar)
I sometimes have UX design students who want to completely reimagine a common interaction like searching or logging into an app. I get the impulse. Aren’t we supposed to innovate? Inspire? Disrupt? Well, no actually. At least not with everything.
The amount of change people can handle is actually pretty small. We learn from past experiences, and we expect new products to work similarly to products we’ve used before. The mere exposure effect tells us we also find familiar words, environments, ideas, and patterns comforting. Familiar interfaces are better for both usability and satisfaction.
Use common design patterns: There are usually one or two common ways to accomplish a task in an app. Do a survey of a few of your favorite apps and you’ll see their search, chat, and navigation menus look pretty similar. That’s because these methods work well and people know how to use them.
- Choose your spots to innovate: When you have a clear reason to do something different (usually backed by your own user research), go for it! One meaningful innovation is a much better way to go than many.
5. Don’t ask your users to do your job!
Henry Ford, the founder of Ford cars, is often cited as having said that if he had asked people what they wanted, they would have asked for a faster horse. Whether or not he said this, the sentiment behind it is informative. The truth is that people are very bad at affective forecasting, or predicting what they’ll like in the future. It might sound like a good idea to ask users directly what they want from your product, but it often isn’t. That’s actually good news for you, though, if you’re trying to get paid to design products.
Observe your users rather than listening to their preferences: Nielsen Norman Group calls this the first rule of usability. Observing users can help you identify the problems they’re having, and then it’s your job as the designer to brainstorm solutions.
- Prototype and test: Wireframe your ideas and put them in front of users as a prototype. Opinions about a specific iteration of your idea will be much more reliable than users’ initial reactions to your idea in the abstract.
Understanding how people think is essential to designing intuitive and usable interfaces. These 5 psychology principles and their corresponding design heuristics only scratch the surface, but they’re enough to get you well on your way as you start to design.
Want to learn more about the fundamental principles of good UX? Take a look at these articles: