The WiiU didn't "underperform". It's selling right in line with the trend Nintendo's home consoles have taken since they first entered the console market.

NES: 62 million

SNES: 49 million

N64: 33 million

Gamecube: 22 million

WiiU: 13 million

The Wii is an outlier. It rode the wave of the "blue ocean" and motion control fad  and stepped away from the "traditional" Nintendo console. When Nintendo went back to a more standard console with the WiiU, they fell right back in line to the trend they had: declining console sales. They didn't have a gimmick (motion) this time around. They had to rely on the strength of their library's reach to the consumer (not a gimmick) and the trend is that that reach has been dwindling since Nintendo became a console maker.

I'd even be willing to bet that the Wii, on its library alone with a traditional controller, would have sold less than the Gamecube. I mean, think about it: what's so different about it from the N64 and GCN before it, and WiiU now? Wii has Galaxy, N64 has SM64, GCN has Sunshine, WiiU has Mario Bros U. Wii hasBrawl, N64 has OG Smash, GCN has Melee, WiiU has Smash U. Wii had Twilight Princess, N64 has Ocarina of Time, GCN has Wind Waker, WiiU has Breath of the Wild upcoming. Wii has MKWii, N64 has MK64, GCN has Double Dash, WiiU has MK8. Wii has DKC Returns, N64 has DK64, WiiU has Tropical Freeze. I could go on.

These are the core games that sell Nintendo consoles, alongside an allotment of random 3rd party games. So, why did the Wii sell 100 million, if not for waggle, when the other Nintendo consoles sold so poorly? It's abudantly clear that the fluke of motion control is why. When that fad died, Wii sales fell off a cliff and Nintendo quickly said "gotta move to the next gen now", because the Wii's library wasn't what was selling the console. It would have continued to sell well if the library was indicative of a 100 million selling console. When it's the games' library that's really strong and leads to those kinds of sales, they don't just disappear overnight like Wii sales did. After 4 years, the PS3 and 360 still sold consistently, for example.

So, to bring it full circle again, the WiiU isn't underperforming. Get rid of the flukey sales of motion controls and Nintendo is right where they ought to be, following historical data. When people say Nintendo should pull out of the console business and go 3rd party (they could still do handhelds), it's not to spite Nintendo. It's because they realize that things have been all downhill for them since they entered the business, and aren't thrown off by the "accident" of the Wii, considering that that success won't be repeated by them and them doing tried and true traditional consoles ain't gonna work. 

My main problem with this argument is the idea that it was a fluke and Nintendo just somehow lucked out. They knew that if they came up with an innovative idea (motion controls) that they could tap into an audience that wouldn't ordinarily buy consoles. Acting like it was just a fluke/outlier is ignoring the fact they Nintendo also came out with the DS at a similar time, which also had it's own innovative features and sold 50 million more units than even the Wii.

My main problem with this argument is the idea that it was a fluke and Nintendo just somehow lucked out. They knew that if they came up with an innovative idea (motion controls) that they could tap into an audience that wouldn't ordinarily buy consoles. Acting like it was just a fluke/outlier is ignoring the fact they Nintendo also came out with the DS at a similar time, which also had it's own innovative features and sold 50 million more units than even the Wii.

Yeah its kind of hilarious how in order to support that pov you need to completely ignore the most succesful generation that a company has ever had in the industry with 250m of dedicated devices sold. Is also ironic the way they are supossed to be losing branch power since the beggining when all their handhelds have been very succesfull thanks to their own games, even 3DS despite having everything against it.

lol.

Aren't these console makers coming up with "innovative ideas"....every generation? At least, they are inclined to do so. But there's a difference between an "innovative idea" and a "gimmick". An "innovative idea" sticks; a "gimmick" wears out. 

Also, the second screen on the DS was a supplemental feature of the device. It wasn't the main use of it. You could play every game without that screen, for example. It was a "neat feature" that wasn't necessary for the core enjoyment of the device. The DS sold on its library. If the PSP could sell 80 million (which has a great library on its own), is it really that farfetched that the DS sold loads better, with a library that is unquestionably better? If the "innovative features" the DS had are why it sold so much, then why has the 3DS sold so little by comparison? 

And you obviously don't understand what a fluke/outlier is if you think I'm just picking on the Wii to try and discredit it. 

Outlier: a statistical observation that is markedly different in value from the others of the sample. Is this not true of the Wii, in comparison to the rest of Nintendo's consoles? 

And how much did they sell in dedicated devices in prior gens, and this gen?

Exactly. They're on the decline outside of that one gen. I'll give the DS credit, because its due. It had some of the best games on handheld, ever. Can't say the same for Wii.

And, they are lose brand power, in terms of consoles. I think you glanced over the fact that I said "they should still make handhelds". But their consoles? They've been declining since the NES, with the exception of the Wii, whose success won't is unlikely to be repeated.