There are a number of videos like the one I linked above of people accidentally shooting themselves. Most of us sit and think, how or why. In the video, the shooter takes full responsibility for shooting himself and even does have a follow up video talking about what happen. If you have been through a carry class you probably have seen the video of the DEA agent in a classroom declaring his weapon safe then shooting himself in the foot. While some of these videos are funny to watch, remember they got hurt and lucky they are not dead.
Is it the guns fault or the shooter? It is very rare that a gun just goes off. Something had to pull the trigger or release the hammer. Modern firearms are literally dropped tested to make sure that they do not fire when dropped. Most of these “accidents” are user error. Thinking the gun is unloaded, unholstering or holstering with a finger on the trigger. In some cases clothing or the holster catches the trigger. In the video above, he was using a Serpa holster that requires a button to be pressed to release the gun from the holster, his finger hits the trigger when he draws the gun from the holster. With the DEA agent, he had the slide open to show it was clear, but had a full magazine loaded. So he releases the slide, which loaded the chamber, then has his finger on the trigger when he holsters, which pulls the trigger. Both instances are preventable.
In L.A, Police had increased reports of negligent discharges after they switched from Beretta 92’s to striker fired Glock’s and M&P’s. The reason was not the guns. It was their training. They were trained to draw their sidearm with their finger on the trigger. If you have fired either of these, you will know that the first pull on a Beretta is very heavy, most striker fired like the Glock have a easier pull. Since their finger is on the trigger, BANG.
There you have it. Practice drawing is important. Just make doubly sure that the gun is clear in the chamber and the mag is clear.