The Games were the Wii Us least problem, or to put it another way, pretty much the only thing that didnt cause more problems (If you overlook the delays).
The messaging and marketing (or lack thereof) alone had a much stronger impact than Nintendo probably expected. Add to that a quick abandonment from third partys, a high price, and the looming arrival of the stronger XB1 and PS4 and its over.
At the same time, getting cornered like that was good, because it brought out some of the best games they made in a long time:
Pikmin 3 is just beautiful, Mario 3D World as perfect a 3D platformer as possible, MK8 and Smash are among their series best iterations!
Even better: they finaly started experimenting and being brave again: First slowly with Dlcs, then more with games like Splatoon and Mario Maker and now of course we are getting a Zelda unlike any we ever had before!
If those are signs of whats to come, I am getting really exited for NX and the next Mario Miyamoto has been teasing.
The new guy.
Sorry for possible mistakes, not a native speaker!