From what I've been able to glean from the 'net, guns were originally designed to defeat armor.<quoted text>
Horse shit , you are describing "possible uses" ,
but these are not the "only uses".
Guns are designed to fire projectiles as accurately as possible at a target period. Some are specifically designed to shoot at targets as it's main function , others specifically to fire very quickly at targets.
As weapons advanced, so did armor. The gun, which at first was more of a hand held cannon, was designed to penetrate the armor of the day.
Most of that armor contained a human being.
So, unless one was just trying to provide ventilation to the occupant of said armor, I think it's safe to say that the intent was to kill or sufficiently injure said occupant.
Shooting targets is just a practice method for improving the ability to kill. Using live targets for practice seems a bit cruel to me. Don't you think?