The First Law of Usability
Don't make me think. This law is the ultimate test of whether something works. Designers should aim to make every page self-evident, obvious, and self-explanatory the moment I see it.
When we use the web, every question mark or moment of thinking adds to our cognitive load and pulls us away from the task we're trying to do. These distractions are small, but they add up, especially when users constantly have to figure out what's clickable and what isn't.
The goal on the web should be to make every page or screen self-evident and obvious. If you can't, at least make it self-explanatory.
Why Is Usability So Important?
To answer that, we first need to look at how people actually use the web.
We don't read pages. We scan them.
People rarely spend time reading most of a page. We scan it, looking for words or phrases that catch our attention. Why? Most of the time, people use the web to get something done, and they want to do it quickly. We know we're only interested in part of the content and don't care about the rest. Scanning helps us find what we need more efficiently. Besides, we're very good at scanning.
We don't make optimal choices. We satisfice.
Most of the time, we don't choose the best option, just the first reasonable one. This is called satisficing. Gary Klein is an expert on how people make decisions. The rational decision-making model we assume is: face a problem, gather information, identify possible solutions, and choose the best one. But when he studied fire commanders at the scene, he found their behavior didn't match that model. They thought of one plan, checked it quickly, and if it looked fine, they acted on it.
Why don't web users look for the best choice?
We're busy, and finding the best option usually takes longer. Even if we guess wrong, nothing terrible happens; usually we just click Back a few times. Weighing every option doesn't improve our odds much either. On a poorly designed site, the effort is wasted. And guessing is more fun.
We don't figure out how things work. We muddle through.
If you've ever run a usability test, you'll notice that users often don't understand how the things they use work, or have completely wrong ideas about them. But that doesn't stop them from using those things, and sometimes they use them very well. Why? Because it doesn't matter to them. As long as it works, they don't care how. And once we find something that works, we stick with it.
The Second Law of Usability
Web designers and usability experts have long debated how many clicks users will tolerate before they get frustrated. On the surface, this seems like a useful rule, but the real issue isn't the number of clicks. It's how much thinking each click requires. It doesn't matter how many times I have to click, as long as each click is a mindless, unambiguous choice. That's the Second Law of Usability.
Users don't mind extra clicks, as long as each one is effortless and confirms they're on the right track. This is the idea of "information scent": clear links give off a strong scent that tells users each click brings them closer to their "prey." Vague or poorly worded links don't.
"Animal, vegetable, or mineral" is a good example of a choice that takes no thought. When users face a choice, make it as clear, accurate, and obvious as possible. On the web, difficult choices often happen when filling out forms. I recommend Caroline Jarrett's book Forms that Work: Designing Web Forms for Usability.
The Third Law of Usability
Get rid of half the words on each page, then get rid of half of what's left. That's a bit of an exaggeration; the second half is there to encourage you to be ruthless. Rule 17 in E.B. White's The Elements of Style is: Omit needless words. Removing words no one reads has a few clear benefits:
- It reduces noise on the page
- It makes useful content stand out
- It makes pages shorter, so users can see more at a glance without scrolling
Happy Talk Must Die
Happy talk is usually an introductory paragraph that welcomes us to the site, tells us how great it is, or explains what we'll find in this section. A good test: as you read it, you can almost hear a tiny voice in your ear saying #@#%@%@#.
Happy talk is like small talk; it's mostly a social gesture. But most web users don't have time for small talk. They want you to get to the point, so keep happy talk to a minimum. The less, the better.
Instructions Must Die
No one reads long instructions. Your goal should be to eliminate instructions by making everything self-explanatory. When instructions are unavoidable, cut them down to the bare minimum, such as the instructions before a site survey.
Conclusion
The three laws of usability are guiding principles for web design. When designing a site, use them as a guide and do your best to make every design and page require no thought, presenting the information users need in a way that's obvious and self-evident.