That's hard to say. I believe that some of them truly did wish for their hearts back. Their methods were dirty, but they really did think that being in the Organization would help them get it back. I know that Axel did. Demyx? Luxord? They weren't high enough in the ranks to be trusted with the real secrets.

Others really were simply in it for power. People like-- ... They only wanted to overthrow the Superior. But in the end, Number I fooled them all. None of them know, they all died before that was revealed.