They lack star power. WWE needs to build up it's younger talent.
We all know this to be true. Unless they start giving the younger guys some chances, they'll never have the big time succes like they had in the past. (Attitude Era and Hogan Era) Sooner or later, the few big names left in the company will start degrading from television, either because of the age (Undertaker, Triple H, etc..) or because of injuries and welness volitions (CM Punk, John Cena, Big Show, Mysterio, Orton, etc..).
WWE will find this out that they are not on the right track anymore, find out when it's too late to even start building up talent.