Guess what? I AM a good parent, of 5 kids, and I have NEVER lost it, if that's what you're implying. I'm sure most people know to separate themselves from a child in that situation but realistically, this does not always happen.
I didn't say accidentally lose it. I'll try to clarify for you. There have been countless children who were killed under their parents' or relative's or whomever who were killed while being abused. I really doubt most of them are saying Damn it, I can't hold back, I'll keep going til I kill them. Many children who have been killed at the hands of the abuse, well, their caretakers often don't call 911 until it's basically too late. Do I think the caretaker waited so that the child would die? No, I don't. I think they waited while hoping the child wasn't fatally hurt, and/or planning how to cover it up.