I think what OP is trying to get at is that pretty much everyone does or has done something or other which is embarrassing and potentially career-destroying.

In Weiner's case, it's conceivable that the first dick pic was posted by a bad actor. Once it's out, and it's clear what's happening, the "well, I didn't mean to post it!" excuse simply doesn't fly. There's really no choice but to admit it and say sorry, and hope your career isn't ruined.