@nittany03 I don't know if you were around during the initial GTCC rollout back around 2004(?). I was, and I was a squadron PERSO so I got to deal with all of that fun stuff. My impression is it's one of those "good idea, shit execution" deals the Nav is so good at.
The goal was to avoid sailors, especially junior E's, having to absorb large hotel bills on their personal credit when TAD'ed for extended periods of time. Advance per diem sounds good in theory except when orders change and now you're having to claw back cash you already handed out...AM3 Smitty done already spent that in the champagne room, bruh.
So it wasn't the dumbest idea, except then 1) take an already-tottering admin process for claims liquidation and make it even more overworked and less efficient, so that 2) the sailor winds up having to put room charges on his personal cards anyway because his GTCC is maxed out and 3) you can't request to increase the limit or put it in Mission-Critical status
until you've maxed it out and the process takes weeks if not months, and by the way, 4) you make the card part of the sailor's credit report anyway. But we want everyone to use the same payment scheme to make it processing easier, so...make GTCC use mandatory!