Because no matter what the raving fanboys will say, lazy devs do exist.
People were fast to jump on Ubisoft for AC:U, and rightfully so, but when a shitty port for a shitty game happens on WiiU then it's the hardware's fault.
For your information, no, i don't believe that Ubisoft is a lazy dev in general. FC4 says a different story. So does ZombiU that, surprise, was on WiiU.
The WiiU is capable of running games that look gorgeous and perform great. Ubisoft is a very capable dev, no matter what.
AC:U and Watch Dogs are shit, plain and simple, and Watch Dogs, which is our topic currently, was never properly optimized for any platform.
Instead of following the, notorious by now, ninjablade hate train people should throw shit on Ubisoft for delaying the game for so long, only to deliver a shitty product (no surprise there tbh, they had clearly shown they don't care anyway). A shitty product that both Nintendo and Ubisoft would be better off if it never had happened. No one is gonna buy it anyway.