Back when I was young and knew everything, I was convinced that a good shot was a good shot, period, and that anyone who could shoot well at paper targets had to shoot well on game, and vice-versa. Now I am not so sure.
Shooting well at targets and shooting well at game require different skill sets. The target shooter must be able to control his breathing and heartbeat, be able to read mirage and wind, have a perfect trigger squeeze, have his shooting positions down to perfection, and be thoughtful and deliberate at all times. Being a good game shot requires that you shoot quickly, from awkward positions, at ill-defined and/or moving targets, and above all, that you be able to kill without hesitation.
This last is a big thing. Taking a life does not come easily to many people, and I have seen many, many otherwise fine shots become completely unhinged when the time came to drop the hammer on something that was breathing. About the only thing you can do about this is shoot until you do everything automatically, but even that is no sure solution.
Probably the best example of the “bad target/great game” shot is an African PH. The ones I’ve seen shoot at paper can sight in a rifle OK, but that’s about it. However, if you want someone to stick a big bullet up the nose of a Cape buffalo that is 10 feet away, coming at full speed, and has payback on his mind, he is the guy to see.