Admittedly, it's not an unmitigated disaster, but the system's 10 million or so sales in three years are relatively paltry next to the success of its predecessor's 73 million.
Suffice to say, Nintendo would appear to have learned vital lessons from the U's relative failure. The company's next console, the Nintendo NX - just a stupid codename for now - could be doing things very differently.
We know that it'll probably launch this year. There might a new Zelda game as a launch title (though it might also come out on the Wii U). It's apparently different to other consoles; a "new experience" - and not just another iteration of the Wii technology.
The specs will probably be on a par with the Xbox One and PS4. It could also, somehow, be a replacement for both the Wii U and the 3DS; some sort of hybrid portable/home console. It might feature smartphone connectivity. It's apparently very easy to develop games for.
And those were the things we semi-know about. And now that section of the article has come to an end.
Now here's a new section: everything else we would like to see from the NX - accompanied by images of some typically wide-of-the-mark, speculative, NX "concept" art, drawn by quoit-fingered idiots.
The European launch of the Super NES had Super Mario World, F-Zero, and Super Tennis. Admittedly, not exactly the widest range of games - but all three were proper classics, and displayed exactly what the SNES was capable of. Pilotwings followed shortly afterwards, and gave further reason to wrap our SNES in a tarp.
The N64 arrived with Mario 64 - a world-shaking classic by anybody's reckoning - Shadows of the Empire, and Pilotwings 64. Again, a limited line-up, but all very solid reasons to inhale the machine. The Gamecube, alas, went for quantity over quality - though there were still gems such as Rogue Leader, and Luigi's Mansion. And Super Mario Sunshine arrived about six months later, like a "late baby".
Oddly, by the time of the Wii, Nintendo seemed to be more content with an any old rubbish approach. A vast stable of lame-limbed third-party releases could've ruined the Wii's launch - were it not for the fact it came bundled with Wii Sports. Nintendo got lucky: that one game alone justified the system.
Unfortunately, Nintendo had no such luck with the Wii U. The big launch exclusives for that were Nintendoland - a weird party game for sillyboys; New Super Mario Bros - a side-on platformer; and Ubisoft's ZombiU - a good game, but hardly archetypical Nintendo fare. The Wii U has never really recovered from those confusing initial impressions.
So with all that in mind, we say: quantity over quality. Whatever third parties have ready for launch, make sure you launch with 3 or so Nintendo blockbusters. Have another biggie ready to release within six months. And keep the momentum going.
Being uncharitable you could argue that the Wii's controller was gimmick-y - but it was also something wholly new, and to use it you only had to be able to wave your arm around.
The Wii U kept that control system... but then also added an unattractive (and expensive) touchscreen controller. For much of the Wii U's life that controller has been under-utilised by anyone other than Nintendo, making it the proverbial "Sad Henry".
There are all sorts of rumours that the NX is going to somehow incorporate smartphone technology, or be a handheld/home console hybrid. Whatever the central conceit of the NX - keep it simple, keep easy to understand, and please... do not include a goo pipe (a pipe that leaks gunk).
Thomas Mahler, from Moon Studios raged like this on NeoGaf: "With Nintendo not having any devkits out there at this point and probably even wanting to sell it in 2016, I can already guarantee that they’ll just not have any software support, since nobody can just jumble games together in less than a year. I mean, you can, but it’ll be garbage."
And if you're going to court third-parties, might it be wise for Nintendo to be speaking to people exactly like Moon Studios, who produced the distinctive and lovely Ori and the Blind Forest - rather than just Nintendo's rumoured "big partnership" with Electronic Arts?
The NX needs third-party support... but what's the point of that support if it's just going to result in the same fetid tedium that you've already got on the Xbox One and PS4?
When was the last bona-fide F-Zero game? Nearly 15 years ago. See also Starfox (though there's one of those in the works apparently). Why no new Metroid? Or Donkey Kong? Or Pilotwings? These are brands with global recognition, characters that work, solid concepts at their core... where have all the Nintendo blockbusters gone?
Here's where: Toiletville.
The NX needs to stand out and offer something distinctive (but not so distinctive that people go "Eww"). Nintendo needs to remember that it's the Disney/Pixar of gaming. There are gamers out there desperate for an alternative, who want that well-produced, family-friendly fare. You know: like you get at your local Harvester.
Nintendo seems to have returned Mario to his 2D roots - but as nice as the New Super Mario Bros games have been, why no proper Mario?
In the past, the Mario series felt like laboratories for new types of gameplay. Has Nintendo just run out of inspiration? Super Mario 3D world was nice, but felt oddly slight. Super Mario Galaxy 2 was six years ago, however. Six! Super Mario Galaxy was three years before that. Super Mario Sunshine five years before that. Isn't it about time that Mario got a proper Mario game again, before he becomes his own tribute act on the nostalgia circuit?
Nobody wants another Nintendo console to launch to an audience that can't stop shrugging. We all want Nintendo back, we want that buzz we used to get from knowing that a new Nintendo machine meant new Nintendo games. Do this, Nintendo. Do this all for us.