I hate to say it but I think you are spot on CS. Yes, the managers and players will have promotion bonuses written into their contracts, but most of them know that if the team does get promotion they will be shown the door. So why kill the goose that lays the golden eggs? All they have to do to keep all that lovely money rolling in is to stay clear of the relegation zone.
We have to be more ambitious. And the first step to doing that, in my opinion, is to find and appoint a new manager who has something to prove and isn't content with simply collecting his pay cheque at the end of every month.