Roughly 1 in 4 adults has some form of disability. So when a site isn't accessible, it's not an edge case you're ignoring - it's a large chunk of real potential customers who hit a wall and leave. And here's the part people miss: building for accessibility makes the site better for everyone, not just the people it's technically for.
The four principles, minus the jargon (POUR)
- Perceivable - people have to be able to sense the content. Alt text on images, captions on video, and never relying on color alone to make a point.
- Operable - everything has to work with just a keyboard, no mouse required, with visible focus states so people know where they are.
- Understandable - readable, predictable, with clear labels and error messages that actually help instead of just saying "invalid."
- Robust - it has to play nicely with screen readers and assistive tech, now and later.
Quick wins you can do this week
Add alt text everywhere. Hit a 4.5:1 contrast ratio on text. Make every interactive element keyboard-reachable. Add a skip-navigation link. Use semantic HTML - real headings, lists, and buttons, not a pile of divs. None of this is hard; most of it is just not skipping it.
The idea I keep coming back to
Designing for disability tends to invent things everyone ends up loving. Curb cuts were for wheelchairs - now they're for strollers, suitcases, and delivery carts. Captions were for deaf users - now everyone watches video muted on the train. Accessibility isn't a constraint on good design. It usually is good design.
Test it for real
Tools like WAVE, axe, and Lighthouse catch a lot. But the real test costs nothing: unplug your mouse and try to use your own site. Then turn on VoiceOver (Mac) or NVDA (Windows) and listen to it. It's humbling, and it'll teach you more than any audit tool. Worth knowing too: accessibility lawsuits are climbing in the US and EU - building it right from the start is far cheaper than retrofitting under pressure.