IN-PERFECT SOLUTIONS
I meant IMPERFECT!
A good example of humans being flawed is perhaps comparing it to a brand new vehicle. I've seen some people who have a truck they bought in their teenage years, and they still have it at age 80s.
The Truck had some minor problem but nothing serious. At least not serious enough to get rid of it.
Others bought a new truck and it was stolen and damaged. No matter how much the person tried to fix it, something always seems to break. The only solution in this case if you don't want any problems, in your life is to Get Rid of the Truck.
The same with humans. Some humans, though no fault of their own are either born defective, become defective because of the environment they were born into, or because of some BAD experience, they become DAMAGED in one way or another and cannot be rehabilitated.
The Person now is a danger to innocent men, women and children in the Society he lives in.
The Damaged person has to be put down as sad as that is.Otherwise we endanger the innocent.
https://www.history.com/news/8-of-historys-most-notorious-serial-killers