Strength and Beauty I guess? They go hand in hand for the Kuja, so you have to be strong and beautiful? Or just being beautiful helps too?
It is a firm and influential belief in Kuja culture that strength equals beauty.[5] They are snake worshipers and many of the women carry very large snakes around their necks.[6] Some of the warriors can even use their snakes to form bows, allowing them to fire arrows.[7] Their society is apparently meritocratic in nature, as Hancock apparently did not inherit the position. This would indicate that rank is determined by skill.