Accessible by design means building accessibility into systems, content, and documents from the start instead of adding fixes after release. In practice, that includes semantic HTML, keyboard support, readable contrast, tagged PDFs, clear focus states, and interfaces that work with assistive technologies such as screen readers.
In cyber security, this matters because inaccessible controls can weaken both protection and usability. If login flows, MFA prompts, password reset pages, or security notices are hard to use, people may get locked out, ignore warnings, or find unsafe workarounds. Attackers also benefit when forms, navigation, or documents create confusion and prevent users from verifying what is legitimate. Accessible by design reduces those failure points by making security features understandable, operable, and testable for everyone. It is therefore both a compliance practice and a resilience measure.