#1 Paving the road to Rousey’s heel turn
If Ronda Rousey were to lose her Raw Women’s Championship, it opens up the possibility that the humiliation or the degree to which she was screwed in the process might justify her to start a heel turn. After all, she has played nice so far, not really being the one to pick any fights beyond the scope of normal WWE competition. She hasn’t cheated and she hasn’t attacked anyone outside the ring (or at least not without meaningful provocation).
Rousey losing could be ground for her to say screw it—I tried to do the right thing and it didn’t work, now I’m going to embrace the dark side. Whether she went heel as a solo bully character or fronting a Four Horsewomen stable, it would, in either case, befit her Baddest Woman on the Planet persona and ability to talk trash brilliantly when she doesn’t have to portray a nice character.