No guarantees in a gunfight.
Case in point.
https://www.youtube.com/watch?v=2FraE77l4fI
Badguy hit 5 times .357 Hollowpoints, arguably one of the most effective pistol rounds in history.
Officer hit one time with a .22.
Guess who died?
Babyface Nelson was hit 9 times and still managed to kill two FBI agents.
Sometimes motivation will make you ignore the fatal long enough to be lethal yourself.
That video is a perfect example of why cops cannot give ANYONE the benefit of the doubt and never allow anyone them the opportunity to draw even a secreted pea shooter.
None at all. Eons ago, I saw one in Jeff Cooper's G&A page where the bad guy (some sort of major league doper) took 18 rounds of .357 Mag in the chest before deciding he didn't want to fight any more. DOA at the hospital, IIRC.
As for wanting a bigger caliber ... when the bad guy got up the second time, I think I'd be wanting a .600 Nitro Express ...