Because more health looks intimidating? Because its easier to fit in a single slot instead of two resistances? Because it gives some nice sustain and unless you have over 3k health already it outweighs the boost from Guardian Angel?
I have no clue really but these came to mind.
Not Changing this until there is a barrel roll move in Pokemon. Started 25/9/2010 http://tinyurl.com/bls9z3e
simple answer is too give much much higher survivability. adcs can be 2 shotted late game with cc, chain cc any dumb adc caught and kill them right away. death of adc = loss of dps. with warmog they won't be getting 2 shotted and can escape.
Hmm alright then. Considering some pros are doing why aren't the sheep following and building warmogs?
I'll quote this from some older topic: ...basically, low Elo is a time machine. It's a facet, an area, a realm of League that is literally stuck in the past. Everything done in low Elo was actually done by good players anywhere from 6 months to a year to 2 years ago - depending on how low you go.