I have an answer to my own question. Something deep in our limbic system prioritizes the male orgasm. When I was younger, I was puzzled by women who said they could enjoy sex without cumming. They took some satisfaction, I figured out later, from submitting and pleasing and loving their partner. I think that's a part of some men, too. I have also read that studies have shown that in general, non sexually, helping others and even pleasing others can be deeply rewarding emotionally. I sometimes wonder if men don't have some of this in the brotherhood of phallus. We want to please our 'brothers' especially if we enjoy submission and sucking cock. Of course, we are rewarded by cum if we bring our Avatar to orgasm. I don't undervalue the Seed, but would you walk away, swallow and walk away happy if you didn't cum yourself? What do you get out of cocksucking emotionally?