A Hollows' hole represents the loss of there heart. In normal Hollows' it is located in the chest area.
What about the Arrancar? Where is there hole? On some it is not located in the chest, which brings me to my previous point. The hole represents the loss of there heart. So is the hole where there heart once lied? Take Grimmjow for example, I assume he loved eating, for there is a hole where his stomach should be. From that deduction , I believe Noritora loved something about his eye.
BUT WHAT ABOUT SZAYEL! WHERE IS HIS HOLE? You see his whole shirt blown off, but do you see a hole? NO! there is no hole.
That makes me think that Szayel is a TRUE man. For I believe his "Heart" is in the only place a mans heart can lie. In his crotch. Which mans he is a man no more, and takes it up the ass.
Do you think I'm right?