Accessibility and the Curb-Cut Effect
Featuring Sam Farber
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.
Frequently asked questions
What is the curb-cut effect?
The curb-cut effect is the pattern where a design built for people with disabilities ends up helping everyone. Curb cuts were mandated for wheelchair users, but parents with strollers, delivery workers, cyclists, and travelers with luggage all came to rely on them too.
Why does designing for accessibility help everyone?
Solving for the hardest case forces clarity and removes friction that mainstream users were quietly tolerating. Closed captions were built for deaf viewers, yet roughly 80 percent of people who use them are not deaf, and voice control built for motor disabilities became mainstream tools like Siri and Alexa.
What is an example of the curb-cut effect in a product?
When Sam Farber watched his arthritic wife struggle with kitchen tools in the early 1990s, he designed fat, soft handles for her, and those OXO Good Grips became a top-selling brand for everyone. The accessibility need produced a product the whole market preferred.
What can product and design teams learn from the curb-cut effect?
Find the users who struggle most with your product, by age, language, technical skill, or physical ability, identify the single biggest barrier they hit, and fix that first, because solving the hardest case so reliably improves the experience for the mainstream. Edge cases are often the center in disguise. CaseBook turns this into a move you apply to your own product, with an AI coach that reads your answer.