First and foremost the problem was the games. There wasn't really any killer apps at launch. Although it had NSMBU, but it was very weak 2D-Mario. The controller made the system too expensive: when it didn't sell, the system should've been sold at around 150€ pricepoint, roughly half of what it was sold at.
The controller was used as a gimmick in most of the games; it worked with the minigame compilations and party games and games where it was used as a map screen, but the games that required your view to switch between the two screens really killed everything good with it. You also could use Wii Remotes to play games, but only multiplayer and you could not choose your controller. Remember how some Wii games let you choose between GC controller and Wii Remote and Nunchuck? Not on Wii U. The best use for Wii U gamepad was to use it as a second screen on Virtual Console and Wii games.
The best thing about Gamepad was it's D-pad.
Ei Kiinasti.
Eikä Japanisti.
Vaan pannaan jalalla koreasti.
Nintendo games sell only on Nintendo system.
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