In plain language
Don't make users re-enter information they already gave in the same process.
Who it affects
People with cognitive or motor disabilities who are harmed by retyping the same data.
How to check
Go through multi-step flows: previously entered data should be pre-filled or selectable ('same as shipping'), never demanded again. Worked example — A university's online course catalog: upload a résumé, then check the rest of the form: if it also demands full manual re-entry of the same fields with no prefill from the parsed résumé, it fails.
Common misconception
Asking for an email address twice “to confirm” feels like good practice, but this rule treats *unnecessary* re-entry of already-provided information as a barrier, not a safety net. Real example: on a telehealth app's video-visit waiting room, the waiting room asks the patient to re-type their name, date of birth, and insurance ID even though they entered all three during account registration minutes earlier in the same session.