[๖ۣۜLucario]

Because of rival competitors such as Kinect, and PS3 Move. Also, people want to play games like cod etc, and playing that on wii is absolute shit.

I think this is the main reason. But also when people think of the wii they think of kidd-ish games so they don't attract hardcore gamers.

That's why the Wii U won't suck as bad... They learned from that mistake and they're brining out better games, for example; The zombie game and other FPS games