Ya'll are missing the point...There are multiple wounds and arrow can inflict on an animal. An animal hit through both lungs will surely die from a combination of pneumothorax (collapsed lungs/can't breathe) and hemorrhage. In the case of major hemorrhaging...*The animal usually will not have time to make it to water, nor will it find the need to (Its not sick, its dead on its feet and it knows it)* Now, lets say you made a gut shot...This is more likely to cause hypovolemic shock, thus stimulating the deer's survival mode, and causing it to head towards water. Hypovolemia can take hours to kill, whereas exanguination (bleeding out) might only take seconds...with a heart hit, for example. See what Im saying? In one case the animal has time to go to water, and in the other it doesnt have time to think (*in my opinion - the animal's heart cannot pump enough blood to the brain to fully function...*when there is a hole in it*). For bear hunter's, you have seen this first hand when the bear makes a "death moan"; this is the noise that comes from "end stage" vocalization by a semi-conscious bear that can't inflate his lungs fully.