Again, nobody knew what the cap was going to be and if the Thunder didn't have freak injuries I firmly believe they would have a ring. So the plan was that the team would still be really damn good (it was) and also have assets in the future to build a better more well rounded team.
I do agree the Thunder probably win a ring by now with Harden but thats only because RW doesn't get hurt and who knows if Ibaka does either. Even you have to admit that the Thunder have been hit with some bad injury luck the previous two years.