Your initial statement is a particularly bad sort of semantic mishandling. The seal absolutely failed, in the way that any reasonable person would interpret th

Your initial statement is a particularly bad sort of semantic mishandling. The seal absolutely failed, in the way that any reasonable person would interpret that phrase. A seal prevents things from getting past it, and it did not do that. Some alternate phrasings that I believe make the (valid) point without this semantic flaw: - The Challenger did not explode because of a simple or unexpected seal failure. - The seal failure was merely a symptom of a larger, harder to fix, much more troubling failure. - The seal failed, but that was not the failure that mattered.