They don't care that it's broken.

The problem affects poor and indigent people, it doesn't affect anyone with wealth or political influence. In fact, fixing it would cost them more, so they would be inclined to leave it.

Nothing really, except the slow moving bulk of bureaucracy and the fact that changing systems again would be a huge expensive task even just to go back to the old system, given that the old system has none of the current cases and may have been entirely removed.