It really wasn't. It was considered weaker than Xbox and Gamecube, but thats because it came out first. It wasn't a generation behind though and it has the best library of games ever.

Wii wasn't ahead of its time, it was a fad that quickly faded away. It's why the Wii got outsold in the UK and why it will be outsold in the US. It's also why the Wii U is struggling. People just got tired of motion controls once they figured out they are just waggling. Sony tried to create a more realistic motion control experience with PS Move, people didn't care. Wii left a bad taste in peoples mouths. Motion Controls aren't the future, they are the past. Even Microsoft has given up on trying to push Kinect as the future of gaming, its just a Siri-box now.

LOL!  Um, I don't know if you're aware of this, but Microsoft is bundling Kinect with all Xbox Ones.  So, it's the exact opposite of what you're saying.  It's also why Xbox One is so expensive compared to PS4.  The cost of Kinect 2.0.

And Wii was very much ahead of it's time.  Advances in technology applies to making development easier rather than more difficult, and engineered to run quieter and consume less power.  The Wii Remote is by far the most popular game controller that's ever existed.  Over 100 million sold, just in the US.  Think about that.  If you take into account Europe and Japan and include that with North America, there are probably more Wii Remotes sold than the entire install bases of Xbox 360 and PS3 combined.

Current sells doesn't mean the wii mote is a fad. It never was a fad. It was and is a damn good control scheme. It's superior than dual analogs for FPS's. The only people to call th wii mote a fad were Nintendo haters. Did I mention it's still very much an option for the U.

Observation:

1. The Wii U is indeed next gen compared to the Wii'

2. Nintendo will have the weakest console on the market again

3. Chinese Food is ten times better than Japanese Food

4. For as weak as the Wii U is.. there were times I thought it kicked the crap out of anything XBONE and PS4 showed us..

5. The Wii U has the power developers need.. it's just an excuse when they talk about how weak it is.. in fact The PS4 and XBONE are actually going to be overpowered if anything..

Anyway... there you go...

Overpowered? Hardly. If anything I consider them both underpowered in comparison to last generation vs a high-end PC.
Remember, the consoles will be stuck with the same hardware for it's entire life, they will feel incredibly antiquated by generations end, compounded by the fact both consoles are using a mix of low-end/mid-range hardware to begin with doesn't help matters.

No, it wasn't. 5 years is a normal console lifespan, a fad would have been 2 years.

Just because the wii was lower powered than the PS360 doesn't mean the U is on par with them. Many developers have praised the U for its power. 

And need I mention again that the wii mote is still being used for the U?

SNES says hi