Because bringing up the longest life is logical. I never die until the gorgon part, not my fault people get seen. Can the hunter give the whole entire team a weapon boost? nope. Can the hunter help boost the whole entire teams cooldowns? nope. Does a single warlock grenade do more damage than 4 shots from the hunter's golden gun? yes. The other two classes are far more useful than the hunter. I've solo'ed oracles with both a titan and warlock. Only bad players struggle on those. My main is a hunter, but it's obvious as shit the other two classes have more uses in PVE.