The issue of the WiiU's failure compared to previous Nintendo consoles is a hotly debated one in gaming circles. While many are quick to blame one thing or the other for what caused the first console of the current generation to come in a distant third in hardware and software sales compared to its predecessor which dominated the previous generation, the simple answer is there isn't one thing which killed it, but four that each wouldn't have done so, but together conspired to make the game a massive underperformance. Here are the four problems which killed the console in order of severity:
The marketing for the WiiU was it's single largest flaw. Consoles have always had two groups to market to: adult gamers and parents. While marketing also is important towards children and teenagers to get them to spend their money, or more often their parent's money, on the games themselves, the consoles need to sell themselves to the actual people who can afford the expensive three digit price tags comparable to any other major electronic purchase. While these groups have growing overlap, they still remain distinct for the time being and need to be catered to separately. For Sony and Microsoft it was easy: for adult gamers the online capabilities of their games, Sony's underutilized game streaming system, Microsoft's (later removed) movement tracking, and the ability to play the latest instalments of the major publisher's annual line ups and their own exclusive titles. For the casual parent: the continuation of what little Timmy and Susan where already playing with a built in entertainment system that at the time of their release had not yet become standard in virtually every television on the market (if there is a TV that doesn't have Netflix accessibility built in today it's the exception, but in 2013 it was a legitimate selling point). Parents and gamers who could afford systems understood what it was they where getting.
Nintendo, on the other hand, dropped the ball. When it comes to adult gamers, before anything had even been revealed about the console many had already made up the choice of whether or not to buy it. Nintendo has a reputation amongst many for what to expect from its games and systems, one that is strong enough that many will choose to buy or not buy their systems based only on that reputation. As a result of this gamers where less interested in what it could do and more in what it would play, which was most Wii games and a few launch titles that where less then one would hope for. The real issue was parents however, who had been the bulk of those who pushed the Wii into prominence. Many where unaware, and even today remain ignorant of the fact that the WiiU is in fact its own console, and not a peripheral to the Wii. Where the Xbox and PlayStation had numbers added to their title to clearly mark the passage of one generation to the next, the WiiU was too similar in the minds of many to have the console being a new system in its own right to hit home. The marketing campaign did not help things, as apart from its colour pallet and the specific titles involved in ads it isn't that easy for those not paying attention to the system itself in ads to tell the difference between the two. It also did not seem to have the features some would hope for, as the ability to use certain services (again, such as Netflix) was something conspicuous in its absence in advertising even if it was present in the console. In focusing too much on selling the WiiU as a gaming system, Nintendo forgot that what people want to spend their money on, for better or worst, is an all-in-one entertainment system, even if Smart TVs and any single one of the current consoles makes that redundant, doubly so with more cable and satellite providers having such features added to their own systems as well. This obsession with being able to watch Hulu and Netflix on anything and everything is odd, but it's the world we live in, and Nintendo's marketing department didn't realize it until it was too late. We can't fault them for not catering to such an odd quirk of modern marketing, but it cost them in the long run.
2. First party support
Success breeds hubris, and nothing in gaming was more successful then Nintendo's return to top of the industry after the underperformance of the Gamecube with the Wii. The response to success differs from company to company within the industry. EA after dominating game publishing sales went from a beloved to the most despised publisher in gaming with bad executive choices (many are too young to remember, but a little over a decade ago Activision was the most hated publisher). Sony's success with the PlayStation 2 was a bloated, far too expensive system that was difficult to develop for that was the PlayStation 3 (the system even going over budget, selling at such a loss it took until 2010 for Sony's PlayStation division to brake even on the system). Sony assumed that their success with the PlayStation 2 would translate to the PlayStation 3, and it cost them so dearly that had the PlayStation 4 not been the unexpected success it turned out to be the PlayStation likely would have ended where it is now. Nintendo's success with the Wii seems to have made them be in a similar state without the bloated development cost of the PlayStation 3. As a result, however, the first party support was lacking in the initial year of the WiiU's launch. With the exception of Nintendo Land which came pre-packaged with initial launch systems, 2012 saw only three games published by Nintendo for their new system. This compared to the Wii this is actually an improvement, the Wii coming pre-packaged with Wii Sports and Nintendo publishing only two other games in the Wii's first year, 2013 saw the PlayStation 4 launch with 10 games published by Sony, and the Xbox One having 5 games of its own that year published by Microsoft. While the numbers don't seem like that much, the perception was enough for many that there wasn't as much support from Nintendo for their console that other console makers had. A lacking first party library at launch isn't unexpected, on the contrary anything different would be a surprise, but the next point didn't help matters.
3. Third party support
If there's one thing that a console needs to thrive, it's games. This seems obvious, but for whatever reason, be it a lack of faith in the system (an unlikely prospect given the initial console sales of previous systems that publishers support), unseen drama between Nintendo and other publishers, or something else we aren't aware of due to the behind-the-scenes politics of the gaming industry. In 2013 the number of game the WiiU was getting was a full third less then the PS4 or Xbox One in the first year all three where going against each other, and the gap only increased in the subsequent years. While the system has more exclusives, it isn't nearly enough to make up the difference. With the NX on the way, likely to either be released in late 2016 or early 2017, it's unlikely much more beyond what has already been announced will be coming to the WiiU.
If there's one final nail that was put into the WiiU's coffin, it's the gimmick that is the WiiU's touch screen controller. While it gives the novelty of being able to play games on a smaller screen while letting others use the TV, there's very little functional utilization that has come from the touch screen. Unlike the second screen on Nintendo's hand held systems, very few games have been made that seem to justify the existence of this change from the Wii. I can think of three games that truly put it to good use: ZombieU, Super Mario Maker and Xenoblade Chronicles X. Even then I'm on the fence about ZombieU being on that list.
This point isn't a slight against gimmicks in themselves. In fact if we're being honest consoles need gimmicks almost as much as it needs publisher support. Systems need to differentiate themselves from each other and computers after all. But the problem is that it needs to be something functional, that developers can make work for their games, that isn't forced onto them. Microsoft tried to do this with the Xbox One's camera system, and that may have cost them a large numbers of sales in the long run even with that decision reversed. Much like the camera on the Xbox One, when one thinks about the number of games that truly utilize the WiiU's touch screen it's hard to think of anyone not using it for simple menu selections.
While I quite enjoyed this system, in fact I have to say it's my favourite system of the current generation, its faults prevented it from reaching its potential heights. Let us hope that the NX works out better then the WiiU did.