|_blame. (Photo credit: bass_nroll)|
Blame is only useful if used positively, like to solve a problem or prevent one from happening again. Or to change one's attitude through repentance.
It's a form of time. Blame found too early can shift the focus away from solving the problem. Too late and it'll be just that: too late. Therein lies the answer. If you find the blame too early, use the information from it to solve the problem. Find it too late, make sure the people to blame can't make the same mistake again.