[Causality1]

>it could be something totally innocuous that caused the door to come off

If making the door come off doesn't make the cause by definition not innocuous, then what are their standards for what is and isn't innocuous?

[DavidSJ]

In this context, innocuous might mean something that would not have any meaningful chance of occurring in real-world operation, and should not have occurred during the stress test. So purely an artifact of the test, in other words.