Blame is common in the workplace and in personal life. It never makes things better, so it's a poor substitute for analysis and action.
Asking "what went wrong" is a much better beginning than "who went wrong". For one thing, it's almost always someTHING wrong that led to someone doing something non-ideal. For another, people make mistake and do non-ideal things all the time, so we should stop acting as if it's a violation of the fabric of the universe. It's a common occurrence. Move on.
When we start with WHAT went wrong instead of who, we stand a much better chance of finding something that is changeable and should be changed. So, never blame. Analyze and take action.
I find many occasions to say this to clients, either because they are reeling from having been blamed for something, or because they are self-blaming.