I personally, I love the wii u very much. But it's easy for me to understand why it gets the criticism it gets.
1: It was overhyped.
I believe that it was shown a year too early. It was shown at a horrible time, and should've been revealed on the year it was released.
2: The presentation.
The name was very confusing. To me and many others, I believed the wii u was an hd, more powerful wii with an interesting controller concept. Kind of like the O3DS and N3DS.
3: The launch.
New Super Mario Bros was getting pretty repetitive at this point with nsmb2 and nsmbu coming out the same year, and nsmbw releasing just a few years before, the one first, nsmbU should just've been called "Super Mario Bros U" for its old an unoriginal concept. And zombieU was okay I've heard, but really... Nobody really cared for it... Imagine if a game like Super Mario 3D World, or Wind Waker HD Came out on launch. It probably would've sold much better, because it had games that were actually desirable.
4: The specs
The wii u has a pretty decent graphics, but are inferior to xbox one and ps4, (note: the ps4 is slightly lower graphics quality compared to the xbox) It seems that the graphics on wii u are stuck between the ps3, and ps4. But the wii u can definitely pump out good graphics when the developers put there mind to it. Games like Black Ops II, Super Smash Bros Wii U, and Mario kart 8 are a few examples. But the processor inside is kinda lacky, like lets use Black Ops II. I own the both the Wii U and PS3 version, and when it comes to loading a multiplayer game, it could take up to twenty seconds longer to start the game up. That is just one example of the processor being inferior to a console that came out several years before.
5: The disappointing hard drive.
They did not even try with this one... with 8 gigabytes for the standard model, and 32 for the so-called deluexe edition, they really shoved this one under the rug. And I think the did this because of my next point.
6: Marketing plan.
Ever since the wii, Nintendo has been marketing there hardware as family friendly, and beliveing that only kids own a nintendo device. Which is very wrong. Either when you make a Nintendo Network, or start Miiverse for the first time, it says something like, "Hey kids, go give you system to your parents to activate your account" them assuming that you are a child. That is why I think the HDD on the wii u was dumbed down. Just watch any commercial from nintendo! You get some really corny stuff that would make hardcore gamers not take them as seriously.
Final Verdict
These are some of the things that I have found wrong with the wii u, and why it gets the hate it has been getting. Hopefully nintendo will learn there lesson with the nintendo nx, or what I have been calling it, the nintendo cross. Now I want to make one lost point, I AM NOT saying that I am happy that Iwata died... I was devastated. But I think that Nintendo needed a new ceo. And if Iwata was alive, he would've been nintendos spokesman, and still host Nintendo Direct. I dont know the source of this, but i beleive that iwata wanted nx to be even weaker than the PS4 and XBOXONE... So, lets hope that nintendo will improve upon what I have stated. We need ATLEAST a 256 GB standard model. We NEED a great launch. We NEED a true next generation specifications. And most of all, we need Nintendo to make Iwata proud.