The Customary Conclusion Heuristic. We stop testing when we usually stop testing. There’s a protocol in place for a certain number of test ideas, or test cases, or test cycles or variation, such that there’s a certain amount of testing work that we do, and we stop when that’s done. Agile teams (say that they) often implement this approach: “When all the acceptance tests pass, then we know we’re ready to ship.” Ewald Roodenrijs gives an example of this heuristic in his blog post titled When Does Testing Stop? He says he stops “when a certain amount of test cycles has been executed including the regression test”. This differs from “Time’s Up”, in that the time dimension might be more elastic than some other dimension. Since many projects seem to be dominated by the schedule, it took a while for James and me to realize that this one is in fact very common. We sometimes hear “one test per requirement” or “one positive test and one negative test per requirement” as a convention for establishing good-enough testing. (We don’t agree with it, of course, but we hear about it.) (Bolton)