I have seen this many times and even find myself doing it on occasion. I think we don't want to be the one responsible and so for anything that has gone wrong we look for a scapegoat.
This is a far reaching problem and it has developed into a blame culture. In the States, it is no longer, "that was bad luck", but now "Someone is to blame, let's sue them".
I think everyone has to take responsibility for their actions, or inactions, and say, "I am in this position because of what I did." When things are going well, we are quick to take credit.
Interesting question, thank you.