With every "hardcore" Nintendo console comes lower sales!
Perhaps the Wii series has lost the interest of some of the hardcore nintendo fans as Nintendo is dedicating resources to that. It seems like a good portion of Wii U owners are actually on this site compared to the percentage of Xbox One/PS4 owners on here.
Even Nintendo fans are very scepticle of the future of Nintendo. Nintendo pledges to be releasing a successor to the Wii U soon which may lose the interest of many loyal fans.
I think Nintendo fans are finding game substitutes and finding more value in the Xbox One/PS4 what do you think??!