It’s not “mistakes.”
Unless is a true subsistence / survival situation hunters have a moral and ethical obligation to make kills as quickly/cleanly/painlessly as possible.
Despite most American males delusions to the contrary, most hunters can barely make competent /humane shots on game animals at 100 yards, 200 max.
Taking unnecessary long range shots resulting in peripheral hits which only cause the animal pain and aggravation is a form of being what is known as a “slob hunter” aka an asshole.
Said assholes not only commonly overestimate their ability but frequently use more powerful rounds in the mistaken belief that it will make up for their lack of ability.
For example, Deer here in TX are small compared to other parts of the country and can be taken humanely with .22 center fires. However there is a sub culture that hunts them with calibers such as 7mm mag. 300 win mag etc on the theory that the extra power will make up for poor shot placement. This is another form of “slob hunter.” They are too ignorant to understand the extra recoil and blast actually makes their poor marksmanship even worse.
So yeah, fuck that dude and his sister.