I think that he felt he needed to fire all rounds, else he would have stopped sooner.
The object is to protect ones self and to survive unharmed if possible. He accomplished the objective, therefore he won.
Depends on your definition of "harmed". Still want to see the bill for the holes in the car and the garage.
I know it's arguing semantics, but I have a little different concept of what "win" means. Kind of like the difference between surviving and thriving when stranded in the woods. In this case, it seems the 5.7 shooter might have "thrived" if he were shooting blanks. I'd sooner call that a "win".
I know, I know.......any landing you can walk away from.........