>>718982249
It was the fact that no matter how hard he tried he knew he would fail because Snake was just that much better then him.
That's why he did the whole one bullet in the gun thing to judge a person, if luck was on their side it didnt fire, and even when Snake jumped from the cliff into the river Occelot would have missed the shot because he still had one more chamber to fire.
He wasnt holding back because he knew Snake could take it, and in the end Snake still won out.
Same with the Boss, people keep trying to claim she let him kill her, no, Snake finally surpassed her.