Central Thesis
"Don't make me think!" — Krug's First Law of Usability
Every page should be self-evident, users should be able to understand what it is and how to use it without expending any effort thinking about it. If it can't be made self-evident, the fallback is self-explanatory, requiring only a little thought.
"When I'm looking at a page that doesn't make me think, all the thought balloons over my head say things like 'OK, there's the ___. And that's a ___. And there's the thing that I want.'"
How Users Actually Use the Web
We don't read pages, we scan them. Users are usually on a mission, know they don't need to read everything, and are practiced at scanning quickly for relevant words.
"We're thinking 'great literature,' while the user's reality is much closer to 'billboard going by at 60 miles an hour.'"
We don't make optimal choices, we satisfice. The moment a link looks like it might lead somewhere useful, people click it, rather than scanning every option to find the objectively best one. The penalty for guessing wrong is just a click of the Back button, so ambiguous links lose by default.
We don't figure out how things work, we muddle through. People use products effectively in ways designers never intended, inventing plausible stories about why something works. Muddling through is inefficient and error-prone, and a site that requires it survives only until a competitor makes users feel smart instead.
Designing for Scanning
- Use conventions: logo top-left, nav at top or left, familiar icons. Clarity trumps consistency when the two conflict.
- Build a clear visual hierarchy: more important elements are more prominent, related elements look related, nesting shows what belongs to what.
- Break pages into clearly defined areas so users can decide instantly what to ignore, eye-tracking shows people never even look at zones they've written off (banner blindness).
- Make clickable things obviously clickable, especially on mobile, where there's no hover state to fall back on.
- Eliminate three kinds of noise: shouting (competing visual emphasis), disorganization (no grid or alignment), and clutter (too much stuff, low signal-to-noise).
- Format text for scanning: more headings than feels natural, short paragraphs, bulleted lists, bolded key terms.
Krug's Three Laws
- Don't make me think.
- It doesn't matter how many times I have to click, as long as each click is a mindless, unambiguous choice.
- Get rid of half the words on each page, then get rid of half of what's left.
The number of clicks matters far less than the cognitive load of each one, three mindless clicks beat one click that requires real thought. "Happy talk," the welcoming intro copy nobody reads, and unnecessary instructions should both be cut aggressively; Krug's own example trims 103 words down to 34 without losing any information.
Navigation Design
"Navigation isn't just a feature of a Web site; it is the Web site."
Since users have no physical sense of space online, navigation has to tell them what's here, how to use the site, and give them confidence the people behind it know what they're doing. Persistent navigation should include a site ID/logo (always linking home), primary sections, utilities (sign-in, cart, help), and search, with one clear exception: strip navigation down to just the essentials on single-purpose flows like checkout or registration.
The Trunk Test: imagine being blindfolded, driven around, and dropped on a random interior page. Can you instantly answer what site this is, what page you're on, what the major sections are, and where you are in the hierarchy? If not, navigation is failing.
Home Page Design
The first few seconds are critical, the "Big Bang Theory" of web design: users form a snap judgment that strongly predicts every later assessment, and a wrong first assumption gets force-fit onto everything that follows. A home page has to answer, at a glance: what is this, what can I do here, what do they have here, and why should I be here instead of somewhere else. The biggest killer is the "Tragedy of the Commons," every stakeholder wants space on the home page, and each individually reasonable addition degrades the whole.
Usability Testing (Do-It-Yourself)
A focus group is people talking about a product; a usability test is one person actually trying to use it while you watch, and the second is what reveals real problems.
"Testing one user is 100 percent better than testing none." Testing one user early beats testing 50 near the end.
Krug's recommended cadence: one morning a month, three users, structured as a welcome, a few background questions, a home-page tour, 35 minutes of think-aloud tasks, and a debrief. Recruit loosely, most serious usability problems affect nearly anyone regardless of demographic match. After testing, list the most serious problems as a group, rank them, and fix ruthlessly starting from the top, resisting the urge to add features instead of removing friction.
Mobile Usability
The same principles apply, if anything people move faster and read even less on small screens. Mobile-first forces useful prioritization but the "mobile users only want on-the-go features" assumption is wrong, people use mobile from the couch too. With no hover state, every interaction that relied on it (tooltips, dropdown reveals) needs a new solution, and flat design risks stripping away the visual cues users rely on to recognize what's tappable.
The Goodwill Reservoir
Every visitor arrives with a reservoir of goodwill that drains with each problem encountered; once it's empty, they leave and often don't come back. Reservoir depleters include hiding information users want, punishing rigid input formats, asking for unnecessary data, and fake personalization. Reservoir fillers include making key tasks obvious, disclosing bad news honestly, saving users steps, and apologizing when something can't be fixed.
"Besides 'Is my site clear?' you also need to be asking: Does my site behave like a mensch?"
Applying Krug to Conversion Funnels
| Problem | Krug principle at play |
|---|---|
| High bounce rate on landing page | Fails the Big Bang test, doesn't answer "what is this, why am I here" in the first seconds |
| Cart abandonment | Friction in checkout: forms that make users think, no trust signals, distracting navigation |
| Low form completion | Hard-to-answer fields, no just-in-time guidance, too many required fields |
| Poor mobile conversion | Hidden affordances, hover-dependent elements, slow load times draining goodwill |
Quotable Lines
"Your job is to get rid of the question marks."
"Clarity trumps consistency."
"You can find more problems in half a day than you can fix in a month."
"All Web users are unique and all Web use is basically idiosyncratic."
Quick-Use Summary
The idea in one sentence: every page should require zero thought to understand, because users scan rather than read, satisfice rather than optimize, and muddle through rather than learn how things actually work.
The three most applicable concepts:
- Satisficing, the first reasonable option gets clicked, so make sure it's also the right one.
- The Trunk Test, a fast diagnostic for whether navigation actually orients a lost user.
- Testing one user beats testing none, a monthly half-day of usability testing surfaces more than months of internal debate.