No. Shoot until no more threat is left. If you're a really bad shot and the BG manages to flea the property after your first three rounds discharged, under your advise, I'd still have to fire the other 7 rounds in my 10 round magazine into the floor or some such.
Shoot until the threat is gone. That does not mean that the BG is gone, just that he is no more of a threat. I would deem him a threat whenever he is standing on his own two feet and/or holding something in his hand that looks like it might be a firearm. *bang* BG goes down, but still has his gun in his hand. *bang* BG drops his gun, but is getting back up. *bang* BG goes down hard and stops moving. The threat posed by the BG just evaporated in a cloud of smokeless powder, so no more bangs, and I still have 7 more rounds in the magazine for any of his friends that might be coming to his rescue.
Even under nca_mm's advise, I'd be pumping 7 more rounds into a prone person who may not yet be dead. The only justification for that is extreme emotional distress and panic, which, granted, is not unheard of in home defense situations, but it's still wasteful. Wasteful of a human life that as yet has not been tried, found guilty, and sentenced for the crime of home invasion-burglary. Wasteful of ammunition that may yet be needed for other purposes. And wasteful of your own life if you disarm yourself by unloading your firearm unnecessarily and there turned out to be another BG in the next room waiting for the shooting to stop to "bravely" come to the defense of his partner in crime.
You do not shoot to kill. You do not shoot to wound. You do not shoot to disarm. You shoot to stop the attack, stop the crime, stop the threat. Period.
