User blog comment:Xilinoc/Ch. 580 - THE LIGHT/@comment-2120712-20140515175639/@comment-1489595-20140517170702

I'm mostly indifferent to Kenpachi's defeat too. I dunno why anybody should be surprised anyway. His toughness is more of an informed ability anyway since his battles have been so inconsistent in power levels. One day he defeats a Espada in brutal combat, another he loses to a punk kid who barely mastered his shikai. He defeats the strongest Sternritter there is only to be taken out by another Sternritter's groupies.

But this is a problem rife with Bleach as a whole and not just a problem with Kenpachi's character.