Do not ask again for information already given
Aliases: no re-entry · copy forward · redundant entry
What it is
The same name, the same address, the same ID number, already collected once in the flow, asked for again, is not a check. It is the system’s ledger written onto the user. Redundant entry requires that information already supplied in the same process is copied forward or duplicated in one action by default; the user must not rebuild it from a blank field.
A fact can be visible on the page and still be demanded again as keystrokes—visibility and exemption from re-typing are different jobs. Re-authentication (type the password again) is an intentional exception, not a licence for ordinary fields.
Why it happens
Re-entry stacks three costs: retrieval, motor input, and re-checking. People already under memory load inject variants at retrieval (a dropped character, a new format) that the system then scores as errors. Copy-forward turns retrieval into recognition: look, that’s it, or edit one difference, rather than reconstruct from empty.
“Type it twice to prevent typos” is a weak reason even for secrets and irrecoverable identifiers, and the substitutes are usually better: confirm email with a message, confirm an address with one entry plus a check. Re-typing a billing address typically produces more errors than a “same as shipping” copy. Browser and OS autofill are the platform layer of the same mechanism; a page that randomises name attributes or turns autofill off refuses the reduction.
Studying it
Walk the process against the redundant-entry success criterion: mark every piece of information requested a second time in the same process and ask whether the second time is pre-filled, one-action copy, or a blank rebuild. Count as exceptions only what security requires, or where the new input is the point (a new password).
Independent variables: whether the second appearance is pre-filled, whether “same as previous” exists. Dependent variables: edit and error rates on the second field, completion time, rejections caused by format mismatch.
Where it stops holding
Confirming a new password is often typed twice because the secret should not be echoed from the first box into the second; the experience is poor and still commonly accepted. Re-authentication to prove the same person may ask for a password or a second factor again, but should not re-collect the address while it is at it. Across sessions, if the user declined to save, copy-forward may stop. Autofill must never submit hidden values the user never saw—copy-forward has to be inspectable.
Applying it
- Prefill name, address, and contact the second time they appear in the same flow. Offer a one-action copy such as “same as shipping.”
- Use correct autocomplete semantics so system fill can hit the fields. Do not randomise field names or disable autofill to “clear the stage.”
- Verify: finish the main flow and list every field that appeared twice. Except password and re-auth, the second instance must be filled or copyable in one action. Then change one character in the first instance and check that the second follows or remains editable without a full retype.