[mikekchar]

Totally agree. Done it myself more times than I care to admit. One small quibble, if I may. Originally "antipattern" used to mean something that looks like a good design pattern, but will actually bite you in the end if you used it as intended. This is not so much an anti-pattern as it is an unfortunate reality (you have to maintain compatibility with external interfaces for the length of the project). How much bit rot have I seen in my career?

[firethief]

I was thinking of set-it-and-forget-it backup systems as the antipattern, as opposed to e.g. designs that regularly force the "backup" system into active use under controlled circumstances. The battery connector represents sort of a backup of the backup though, so it may not be a good example of what I was thinking of.