What are the odds that somebody breaks into your house, unexpected, and that you have plenty of time to to find & charge your weapon? Hell, maybe your gun would be in a drawer in the same room where the robber is at that point. Seems unlikely and something like that happens only in the movies when you exit as a hero and local newspapers. I wouldn't expect robbers to enter armed in the house, without knowing if somebody is in the house, and start searching for hiden money while giving you time to kill them or chase them away.
Not only that, people talk about it so easily, like you're pulling a trigger to kill a barking dog. You might end up alive but with lifelong traumas & insomnia.