Foul-ups in testing are not uncommon, especially when the test setup is being tried for the first time.

Sometimes a malfunctioning test setup actually gives the tested system a chance to show what it can do in an unrehearsed emergency. During a test of an Apollo escape system in the 1960s, the escape system successfully got the capsule clear of a malfunctioning test rocket.

One of the headaches of high-tech test programmes is having to debug the test arrangements before you can start debugging the things you're trying to test.

Henry Spencer Quotes