They didn't bother to learn how to care for him. When he turned on them, they blamed HIM, not themselves.

So this dog was given no exercise, locked in a crate. His owners provided no leadership for him. NO rules, boundaries or limitations (except the limitation of being stuck in a crate). When behavior problems emerged, they didn't bother to seek out the assistance of a professional behaviorist or trainer.
When he finally tried to bite, they blamed him, and he was the one who was killed. They whispered in his ear: You had everything.
No he didn't.
http://pitbullhatersexposed.blogspot.com/2014/09/anti-pit-bull-piece-is-embarrassment.html