Knockout should be high because you can be way down when it happens. For all of the other ones, you need to be relatively close. Even for a Hail Mary you have to be within a touchdown.
The most electric moment for me as a fan is not the pure KO but when a boxer is way behind on the scorecards in the late rounds and then he catches the opponent with something that wobbles him.
It's like for the next minute anything is possible.