Accessibility and the Curb-Cut Effect

Curb cuts, the little ramps at street corners, were mandated for wheelchair users. Then everyone started using them: parents with strollers, delivery workers, cyclists, travelers dragging luggage. The pattern repeats everywhere. Closed captions were built for deaf viewers, and now roughly 80 percent of the people using them are not deaf. Voice control built for motor disabilities became Siri and Alexa. And when Sam Farber watched his arthritic wife struggle with kitchen tools in the early 1990s, the fat, soft handles he designed for her turned into a top-selling brand for everyone.

For anyone building a product, this is a case about the users who find your product hardest to use today, by age, language, technical skill, or physical ability, and the friction they hit that everyone else just tolerates more quietly. It sharpens which single barrier to fix first. Why designing for the hardest case so reliably improves the product for the mainstream, and what that says about the rest of your design, is the part the app holds back.