Well said. If the dog is not getting enough oxygen to its muscles it must stop. A car must stop when it runs out of petrol.
I cannot see the point of a dog that runs itself to the point of complete exhaustion. I would rather have a dog that works out that the odds are in the quarry's favour and quits. Much better that way because the dog is fresh enough for a run where the odds are more in its favour.
I know there's this big macho thing about never quitting and some owners seem to think it's a refection on themselves--some sort of half arsed John Wayne syndrome. It's bollox.
Dog that pick