Hmm good question. I was wondering this myself in addition to some other things floating around my head. Why is it necessary to exercise in general on a bulk? Other than the obvious reasons of course. And why is it necessary to eat protein, and don't just give me the "obvious" answers. Oh, and why should I try to add weight to the bar every week?
I mean, I know the obvious answers, but I'm not sure if it's necessary unless you give me some abstract and indirect explanations. No trolls please, this is a serious question. I'm super serial guys.