Now that the smoke has cleared, it's easy to see that WWE failed miserably with the Legacy stable.
The point of a stable is to add a new twist to the main star and to elevate the other members of the group. Take Evolution, for example. Triple H gained more heel heat. Ric Flair became relevant again. Randy Orton and Batista found a vehicle to eventually become main event players. Everyone benefited from the pairing.
Legacy was supposed to have done the same thing as well.
Orton had grown stale and needed a change. Cody Rhodes and Ted DiBiase needed something to complement their marketability factor (being multi generation names). Legacy was supposed to enable them to scratch each other on the back.
Unfortunately, it failed.
The only person that benefited from the stable was the guy that needed it the least - Orton. He was already a main event performer, but with some helping hands, he was able to maintain a spot up there without resentment from the audience. That gave the creative department time to come up with a new twist in his character that we currently see.
Rhodes and DiBiase, however, have fallen back down to earth. Neither guy has accomplished much since Legacy disbanded. Rhodes has potential because of his superb and underrated mic skills, but it's still hard to envision him as a future world champion. DiBiase was given the future world champion label almost immediately upon his debut, but his lackluster performance thus far on Raw have been quite discouraging.
In conclusion, Legacy was a wasted opportunity.