Why does it persist in the keyblade graveyard, I thought since Terra's body was transported out of the Keyblade Graveyard, the armor should leave as well?

Im guessing It's becuase when Terra's Body was made into terranort remember when the armour came to life and Terranort said "Your body submits, your heart succumbs, so why does does your mind resist?!2 I think that means Terra's body and hearts is now Xehanorts but his mind or part of it is inside terra's armour.

I don't know, maybe because it prepared itself for the blast by sticking the keyblade to the ground, oh, and it's a sentiment, maybe it can't leave without having Terra back.

I don't know, maybe because it prepared itself for the blast by sticking the keyblade to the ground, oh, and it's a sentiment, maybe it can't leave without having Terra back.

 

Building on what Rob said, since it's a sentiment (or what ever you call it), it is just emotions. I doubt it has any idea how to get out of the Graveyard, or can even consider to leave.

It could be like a ghost, who cannot leave the place it lost it's body.

i think becasue his mind is still in his armor and maybe he need someone insaid the armor so he can get out of keyblade graveyard , and MX has take his body now he can't get out until he found 2 things : 1-His Hearts 2-His Body . then he can get out from there