The big idea
Using first principles in UX will make your product more intuitive and more enjoyable for your customers, while making your job easier.
First Principles
If you're not familiar with the term, First Principles are a way of thinking about a topic by breaking it down into its most basic, fundamental elements.
Instead of reling on assumptions, first principles encourage you to rebuild from the ground up, focusing on what is well known, true and fundamental.
Using First Principles in design should give you a set of rules that can help you make better decisions about how to build your product. Let's look at a few examples:
1. Everything on screen should have an obvious function
When people interact with your UI, they shouldn't have to guess how it works. An obvious interface means every button, icon, and element should look and feel like it belongs -- and functions in a way that's consistent with what people expect.
For example, if a setting can be toggled on or off, it can be tempting to render a button that shows two states - from a developer's perspective, it's easier to code, but the result can be confusing for the people using your product.
Instead, use a toggle switch to instantly communicate what the function is.
Small details add up to a more intuitive experience - does the mouse cursor change to a pointer when hovering over a button? Is there a visual difference between a clickable element and a non-clickable one? These small details can make a big difference in usability.
You're taking advantage of things we are already used to: toggle switches switch between states, and seeing a pointer when hovering over something indicates it can be clicked.
2. Your interface should be consistent
Once you've nailed down the patterns for individual bits of UI, they should be used consistently throughout your app.
If you're building features that your customers will use, you should build them with the same attention to detail as the rest of your app. I leave some room in my heart for easing up on superuser features that will never end up in the hands of a paying customer, but even that can be a slippery slope.
So - take the time and get your UI primitives working well, and use them consistently throughout your app. Heck, do yourself a favor and take advantage of a component library like Shadcn.
3. Your customers are already trained
People spend more time in other apps than in yours. It's a reality that sounds depressing, but is actually good news for you. Your customers have been trained by thousands of other apps and websites - they expect certain patterns and conventions when they're getting things done.
They know what an inbox looks like, and a calendar, and a search bar, and a settings page. People come with built-in expectations for credit card fields and push notifications and date pickers. Use these things to your benefit - don't reinvent the wheel where you don't have to.
More reading on first principles
You don't need to listen to me (ever) - but you should at least consider learning from people smarter than me:
Thinking with Type
When I was studying Human-Computer Interaction in grad school, I read Thinking with Type as part of a course I took on cognition. The professor who taught the course use to repeat the phrase "Words have meaning" often. He had a habit of showing us examples of how people's expectations for how things should work are shaped by the types of experiences they've had in other places. Words have meaning, and the way we present words carries more meaning than you might think.
Dan Mall on Design Systems
Dan Mall is a designer who has written a lot about design systems. He's got a great primer video on his YouTube channel - What is a design system? is worth a watch for nailing down some first principles goodness.
Hey though, go vote
We're less than a month from The U.S. presidential election. If you're one of my American pals, please go vote. If you're not, please consider reaching out to someone you know who is and asking them to vote.
You're going to be bombarded with ads for the next month - it's easy to get cynical and tune it out. Please don't. Your vote is too important.
Need to look up your polling place, or see who is on your ballot? I got you -> vote.org is a great resource.