How well do you know your home. Can you move around your home in the dark? If there was an intruder in your home are you one of the guys that will flip on a light switch waiting to get shot?
A homeowner has the advantage of knowing his or her surroundings. The intruder doesn't. If you have to turn on a light to see someone breaking in. You just gave up that advantage.
Granted if you have kids, or house guests.This task becomes more difficult. But I think you get my point.
I can walk freely in my home. I know where everything is. If I had to seek cover. I know where it is.