Yes Wii U owners aren't buying third party games, the real question is why is that?
I think a lot of it has to do with that most people don't buy just one console anymore. How many people own just a Wii U really? When most of these third party games play better or have DLC only on Xbox or PlayStation how do these companies expect the games to sell on the Wii U when they are inferior. I think Nintendo has made a lot of mistakes with the Wii U (despite it really being a great system overall) but I don't think the blame is with them alone.
If we look back to the Wii U's launch what kind of third party support did the Wii U get? Ports, ports of older games some that had been our for more then a year and these companies wanted 60$ for them despite how long they'd been out (Mass Effect 3 was 60$ on Wii U when it was 20$ on PS3 and 360 at the time and they had just released the freaking Trilogy on 360 and PS3 for 60$ and it was also the end to the freaking trilogy only on Wii U). While there was a game like Zombie U that was exclusive (which I'll talk more about below...) for the most part all the great 'third party support' was ports which were generally more expensive and inferior to the already released 360 and PS3 versions.
How the hell did these companies expect this to succeed?
Outside of EA which backed away from Wii U quite quickly for whatever reason (not going to talk up rumors since we don't know for sure what exactly happened) all of the other companies seemed to think everyone who was buying a Wii U never owned a PS3 or 360 to play these games... Every company who thought that doomed their own sales and hurt Nintendo the moment it happened. Why the hell would any of us buy these games again, GAMERS buy systems at launch, not the casual players which were a majority of the people who only owned a Wii. We owned all of these titles and even if we didn't why would we pay full price on Wii U when they were significantly cheaper or had better versions on other systems. It was a largely bull shit effort by third parties that were then shocked that these ports didn't sell well and then everyone started dropping support for the Wii U. I think part of it was also that the 3DS wasn't doing so hot around this same time either and many of these companies expected Nintendo to fail so they didn't bother to put any real effort into what they were doing.
The lone exception was Ubisoft at launch with a new title Zombie U. Zombie U was rushed out for the launch of the system and ended up being pretty mediocre overall(I think I'm being generous with mediocre I hated the game), even despite that it was the best selling third party game for the Wii U at launch but didn't do the numbers Ubisoft wanted.
So Ubisoft also weakened their support of Nintendo, with a move I think drastically hurt Nintendo (and likely their own sales for the game) by changing the once exclusive Rayman Legends to multiplatform and then delaying the already finished Wii U version due to some BS about Microsoft's multiplatform release requirements. I don't think I've ever seen the sales data for that game but I doubt that move ended up helping the games sales that much (the first game sold really poorly) and I know they lost my money on it as well, I had the game paid off before they delayed it on Wii U and because of the delay I still haven't bought it.
Most recently Ubisoft has come out and said they have games COMPLETELY FINISHED for the Wii U but have not released them due to the Wii U's poor sales. One of the titles likely a part of this is Watch_Dogs which lets all be honest here was likely done for Wii U the same time as the other versions and Ubisoft simply 'delayed' it to punish Nintendo, they have said it themselves they haven't released finished games for the system due to it already would it really be surprising if Watch_Dogs was one of them?
This is what baffles me about Ubisoft, they show minimal effort for the system at launch, take away its exclusives, and hold back games that are finished for the system due to sales. (DESPITE that the Wii U has life to date sold more then Xbox One, I don't want this to become a console fight but I think its insane they bash and hurt Nintendo so badly and still give plenty of support for a system that has not even passed its sales yet and isn't exactly increasing at a very speedy rate). Then they claim some BS about Wii U owners not buying their games.
*ahem* (begin rant)
If you freaking released something without delaying it that wasn't an inferior port that also included the DLC for it and stop assuming that people who own a Wii U own nothing else some of your crap would sell better.
Perhaps if Zombie U wasn't a pile of rushed out garbage that should have been some crappy arcade game and you had not released the game at launch when it clearly wasn't ready and going against freaking Mario for sales it would have done better.
If you had actually released Rayman Legends as an exclusive since it was freaking finished it would have sold Wii Us and sold more of your own games for the system (such as the crapfest that was Zombie U).
How do you expect anyone to buy the system which clearly is struggling for support to sell more systems without software... software that you HAVE COMPLETED AND FINISHED AND REFUSE TO RELEASE.
*ahem* (end rant)
I think many of us give Ubisoft way to much credit. Did they try? Yes, they give slightly more effort then EA and the other third parties. Its not like they really tried though. If they were really committed to the system from the get go they would have released Zombie U a few months later when it wasn't going up against Mario at launch and could have been in a much better state (seriously that game would have been infinitely better if you had more then 1 option for a melee weapon).
Rayman Legends could have easily come out later on as a special edition 360/PS3 while still releasing the original game on the Wii U back in Feb 2013 like it was originally slated, but Ubisoft wanted to punish Nintendo for Zombie U selling poorly (which again could have done better if they bothered to try).
All of the ports like Assassin's Creed and Splinter Cell could have had the DLC available for them increasing their value but Ubisoft said no and didn't release any of it, and AC3 came out a month after the original game did (due to the systems release date) which many people had already bought and had been on sale at several places for 20$ off by the time the Wii U version came out.
They have finished games they won't release on the system until it sells better despite that THE SYSTEM CAN'T SELL BETTER WITHOUT SOFTWARE TO SUPPORT IT.
Ubisoft may have boned Nintendo the least compared to the rest of the third parties but they have boned them none the less and they don't deserve any sympathy from us, they created their own problems with the decisions they made and have no one but themselves to blame for what happened to the sales of their games on Wii U.
(TLDR: Ubisoft is Ubisofts own worst enemy and in the process hurt Nintendo and the Wii U along the way, they also can go die in a fire for having finished games that could help the system sell that they refuse to release).
