Except in real life people sometimes make malicious "mistakes" deliberately and when caught and called out on them either completely dismiss them or even gloat. This reads almost like a fairy tale.
In my experience very few serious mistakes are deliberate and there is a huge gain to find a way to not make the same mistake again. Which include avoiding blame, but rather go looking for the root cause. People who can handle serious mistakes in others are some of the best partners you can have in your efforts. IMHO they aren't fairy tales.
Instead of blasting people for mistakes they set about fixing the immediate problem, and then instead of demanding "accountability" from those responsible, they set about fixing the root cause.
A few excerpts from the linked article:
"Aside from the fact that there was immediate chatter about who might have made such a dumb move, the discussion quickly moved right on to how to fix the problem."
"Instead of dwelling on pinning the blame or lamenting the loss of time and effort, the team made sure to alter the backup strategy so that something like that didn’t happen again, and it went about making up for lost time."
[0] http://thenextweb.com/media/2012/05/21/how-pixars-toy-story-...