The more heart / lung damage and bleeding. The faster the game goes down. That's besides breaking it's neck or spine.
The more weight a bullet retains. The more energy it delivers.
Just for kickin' the can.
If you deliver two bullets at 1500 ft / lbs
After impact one looses 50% weight...
After impact the other looses 10% weight...
The bullet that retains 90% weight is going to retain more energy. Therefore, pass throughs are more likely and as much or more energy is delivered throughout.
There are hunters up here that swear by pass throughs. The reasoning being, it's easier to track. Barnes X and Failsafe being their preference. Yet I have seen mushroomed Barnes X's and Failsafes that were dug out of downed game. So there are no absolutes.
Bleeding whether it be internal or external is as important as hitting a vital area.
My preference goes to Bear Claws, Partitions and now the new Accubonds. They have a large mushrooming and retain a large amount of their weight. More tissue damage and more retained weight for retained energy.