“The road from white belt to black is long and arduous; most never reach the end. There are simply too many obstacles of daily life, and too much effort and attention required, for this to be something that the majority of practitioners achieve. This is why a black belt in Jiu Jitsu, especially from a reputable source, is the pinnacle of martial arts rank. It is valuable because of what must be traded for its achievement.”
Book:The Tao of Jiu Jitsu