Bad trigger discipline! I'm glad he took the clip out, but this is how accidents happen. What if a round is chambered? The bullet could go from the basement he lives in, through the kitchen floor and into his mom's ass.
And the only thing he thought he had going for him is nulled by showing us he doesn't know how to handle firearms. But maybe the finger is resting on the trigger because he has to be "always ready" due to lack of any mobility.