Angela Glover Blackwell used the term in her 2017 article, The Curb-Cut Effect for the Stanford Social Innovation Review. The "Curb-Cut Effect" illustrates when accessible design benefits a broader group than was originally intended. Curb-cuts, originally created for wheelchair-users, are broadly helpful to people with strollers, luggage, hand trucks, etc.
Another example of this effect is closed captions. While they were created for people with deafness or hearing impairment, studies report between 60-80% of people regularly watch videos with captioning on, often to assist in understanding dialog or provide access in noisy environments.
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