They had one and the ratings tanked, Bellator 360, they are trying to build up Paramount Network as a big channel, when Spike had the UFC they basically showed two seasons of TUF with finales, at most 4 other free fights on Spike and eventually an hour of preliminary fights on PPVs, the market wasn't full, Spike could air Countdowns & Unleashed etc and the fans could only get that stuff on Spike.
UFC on Fox Sports doesn't do big ratings outside live sporting events, so can air all the other stuff the UFC puts out.