Product Discovery & User Research
Last reviewed
Correct answer: B. Test no more than five at a time, and run many small tests
Explanation
The principle — the number and the cadence are one finding, and quoting either alone reverses its meaning.
Why the key is correct — the result is that The best results come from testing no more than 5 users and running as many small tests as you can afford. Both clauses are in the same sentence, and the second is what keeps the first honest: a small round is only cheap enough to be worth repeating.
Why the others are wrong — testing five once and stopping uses the number against the sentence it came from. Treating five as a universal sample size applies a claim about usability rounds to research it was never about. And a survey is a different instrument with different sampling behaviour.
Remember this — five per round, many rounds; never five and done.
Sources — Nielsen Norman Group on testing with five users.
Sources
“The best results come from testing no more than 5 users and running as many small tests as you can afford.”
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