Wii U is just too weak compaired to the Xbox One & PS4.
Theres no way around that truth, then add ontop of that its crazy hard to develop games for and... yeah.
It isnt getting as many 3rd party games.
I hope nintendos next system is either ARM or x86, not some IMB Powerpc type weird cpu.
I also hope they go with a APU from AMD, and work abit on ease of development for the system.