Fallibillity, does not imply any particular mistake. No real-life failure can ever be blamed on fallibility. which may sound kinda "duh". but ppl ignore this quite often.
for example, sum1 might mention hitting his kid once, and say he was taken over by passion (a diff error) and that mistakes happen (bingo). the fact that mistakes happen, in no way excuses this particular one, whihc was avoidable.
the problem with the passion excuse is all the passion means is that he was in the right environment to act on a facet of his personality that he usually doesn't.