One of the reasons I own a Glock is that I have learned that simpler is better. I want to draw my weapon and shoot. No real thinking involved. If it doesn't shoot, I do the malfunction drill and if that doesn't work I throw the gun at the perp. (Hey, it works in the old time movies!! :danceban:)
I recently took a defensive rifle class. Obviously the AR15 has a safety and we used it the whole class. The rifle was on "safe" unless we raised it and aimed it at a bad guy.
During the drills, I would raise my rifle, aim and pull the trigger but nothing happened. I performed the malfunction drill and still nothing happened. Then I realized that I did not disengage the safety. This is a training issue, I know, but it makes sense to train the same way with your handgun as you do with a rifle. And under stress, things can go south real real fast.