"You have to be a parent to understand." Does anyone else find that some (not all) parents use this line or a line like this to justify for their own abusive behaviour?

Or is it just me who has noticed this? Am I being unfair? Maybe I do have to be a parent to understand some things, but do I really need to be a parent to understand that some parents who say this say this to explain how helpless, powerless, and out of control they feel sometimes? Sometimes to the point where they overreact and make mountains out of molehills? Am I really ignorant? Or do they find it hard to imagine non-parents can understand them? It’s like they view it as impossible at times…

And if you are a parent who says this, what do you really mean when you say it (if you ever do)?