Well, because from my point of view, Alder doesn't deserve to be a champion in the first place. Just look at his clownish behavior: Hitting on every woman he sees, falling asleep during battles, not taking battles seriously, being gluttonous and so on. It's this kind of ridiculous behavior that's not worthy of a real champion.
In contrast, Cynthia is serious, superior, gracious and powerful and that's why Alder will never be able to hold a candle to her.