It's funny how the most genetically elite bodybuilders still have flaws. Just goes to show how rare perfect genetics are.
Take Ronnie for example. Arguably the best bodybuilder ever but still has flaws:
-small calves
-funky shaped abs
-big legs but lack the cuts and feathered effects guys like Cutler and Cormier had.
-gyno
-slightly small triceps compared to the rest of him
-pinched shoulders
Actually his triceps were quite large. It's that he didn't have prominent long and lateral heads (the horseshoe), but had a very prominent medial head. Look at his triceps when he does a front double biceps.
Also, could this also explain why he has a good chest as well? Notice that those who have prominent long and lateral heads, they tend to become more developed during chest work---as they seem to be activated more. One must also take into account arm length as well.
Flex was narrow as well, and people with his body type tend to have a hard time losing fat/water in the lower back, glute, and hams.