Kennel accidents do happen to the best of us but the right mindset is to realize it was a slip on YOUR part and you need to change things up to ensure it doesn't repeat itself. Don't accept these mistakes and poor management as things that will always happen to all of us because that thinking is what allows it to be repeated. I know of a lot of seasoned dogmen who have accidents yearly. It's not because they want it that way, but they either get lazy or aren't OCD about making sure shit is 110% all the time and then they give themselves excuses.