Earlier quoted context omitted.
So, the Wii U is so many failed consoles now? The Wii was a raging success. The 3DS is a wonderful mobile gaming platform that I have poured hundreds of hours into. The Wii U wasn't great and was more of a half iteration than a full one. Yes, Nintendo made a mis-step there. But the Wii, DS, and 3DS were far from failures.
The Wii was very successful. But was very underpowered when compared to the 360 and PS3. As a result it did not get many popular AAA multi-platform games such as Call of Duty, Grand Theft Auto, Assassins Creed, etc.. and when it did get games from those franchises it was a simplified or less feature filled version of the game. It meant that the Wii was not really viable as your "only" system if you were interested in…
People who don't know about other franchises, and perhaps don't want the more mature subject matter of the three big franchises you mention, were more than happy with the fun a Wii gave them.