There are people that you take to the range and work on muscle memory for 6 weeks and they keep those good habits for a lifetime. There are others that dump all those good habits right away. The first group don’t shoot themselves or others accidentally.
There is always the possibility DumbCop was trying for his Dog Shooter badge and attempted a task beyond his mental/physical capability.
With the advent of cheap laser training devices like the little Laserlyte barrel insert thingie, anyone can now practice at home. For the non-professional shooter, it is the best invention since sliced bread.
Better, actually.
When I was 10, my Dad taught me to field strip a 1911. He showed me, then had me hunker down (newspaper on the floor to make it more filed-like) to try to repeat. My butt hurt, then my nose hurt - he gave me a short kick for not checking the weapon prior to working on it. Today, he might get in trouble for "imprinting" the lesson, but it's over 50 years ago and I have never touched a weapon without checking it and treating it like it was ready to fire.