Another thing people forget...even if you get lethal shots on them at the same time they get to you...they can continue because handgun shots (and all shots for that matter) are very rarely immediately incapacitating.
Unless, of course, you are shooting a .45 in which they will vaporize and the bad guy behind him will catch fire. (note the lack of purple...I've seen it!)
I watched a charging 6'2 350lbs nutjob take two .45 acp rounds center mass drop like a rock. Heck it was even a 1911 with a manual safety!