Remembering to disengage the safety on the range is easy. But wait until you're in a high stress situation and go straight to pulling the trigger and nothing happens. I saw a video of just that. Bad guy tries to rob store owner and store owner forgets to disengage safety. Fortunately for him, the robber was a bad shot and the victim eventually remembers to disengage the safety and returns fire. For that reason I'll never carry a firearm with a manual safety. I can count on my Glock to go bang when I pull the trigger.
I practice at the range to click the safety off as I pull it from the holdster. It’s became automatic but I understand exactly what your saying. I love glock and have never had a issue of it accidentally going off. But was actually afraid in a high stress situation that I may grab it to pull it and give my self a new butt crack. Or something catching or snagging the trigger although I have never heard of a story of that happening.