Action Is Always Faster Than Reaction

i remember first time i was in combat and killed a dude. He was behind a door, and he was hiding behind the door. And immediately, i reacted so fast because i had no time to think that i didn't get an opportunity to look through my optic. So as i just reacted and flicked a safe de semi and start e gun ing hem down. Ye, action is always faster than reaction. After i did the after action on that unlike man, this whole process that we teach people to look at a circumstance,. That might be a paper target in training, that has hands that have something bad. Then we process that information, and then we manipulate our gun to our eyes