I've shot lots of animals with every produced bullet from all the different manufactures and they all killed them dead.
While 'killing' IS the primary goal of shooting (hunting)animals, 'how' the bullet performs is very important.
I am speaking for a total of one, myself, I demand a bullet to hold together and not to explode or separate in several pieces. When hunting 'stuff' happens and sometimes the bullet does not hit precisely where we want it to hit. Maybe there's been deflection by something unseen. Maybe the animal takes a step or turns at exactly the wrong moment, et.al.
The more violently the bullets opens/explodes the more/greater tissue damage is done. That's fine IF it's in the lungs but I don't want it to pulverize the shoulder, backstrap, or ham. And in some of those instances the death may occur much later and the animal might not be recovered.
We as hunters must determine what we call/determine what is acceptable bullet 'performance'. For ME, just because the animal dies does not mean the bullet performed properly.