In my CS university software engineering course we defined several versions with different meanings: error, fault, defect, failure, etc. Some are about the programmer doing something wrong, some are about what the code itself contains after this, others about the actual event when the problem gets triggered etc. I forget which was which. Something like the error is what the programmer makes, the failure is what happens when it gets triggered when used, the defect is the thing in the code (colloquially: bug) if I remember correctly. No idea what "fault" was.
I’m not sure if there are standard meanings for these words, but ISO26262 defines Fault, Error, and Failure in specific ways that are useful to think about but I always struggle to keep straight. Well mainly I swap fault and failure if I’m not careful.
But in this case, none of these are design or implementation mistakes. We just call those bugs, though maybe there is an official term like defect for them.
