With regards to the Wii U, most of what happened was remembered for various reasons.

Lets recall 2012-2013

The Pros:

Sufficent third party support compared to now.

Most powerful console at the time.

Tablet controller allows for play without a television.

Few delays relative to releases.

The Cons:

Poor advertisment of the system resulted in the failure of the Wii U to capitalize on its headstart.

Wii U was the most expensive console at the time.

The power gap between it and the last gen consoles, barring the Wii U, wasn't enough to overcome the price difference against console which were not only drastically cheaper, but had a much larger user base, which took a lot of the Wii U's multiplat consumers. This is assuming that a substational portion of those who bought a Wii U had a PS3 or 360.

This resulted in poor sales of multiplats on the Wii U and led to much of the situation it is in right now.

The releases were scheduled farther and farther apart eventually leading releases in seasons rather than monthly or bimonthly.

While we have yet to see how the Wii U will do in its second year, Nintendo completely squandered the Wii U, underestimating the competition and priotritizing the 3DS, which wasn't where they wanted it to be atm. Although, its not too late for it to sell well, the usual Nintendo Lifecycle of 5 years will not be enough time. The best thing for Nintendo to do is upgrade their infrastructure and support the Wii U, the same way Sony did with the PS3, in order to better prepare there next console for release.

Indeed, Nintendo have themselves to blame here. As far as I'm concerned, marketing has been and still is the biggest issue for Wii U, though they made some strides in the right direction with Mario Kart 8. The other huge issue was release schedule, which despite the lack of third party support, is steadily improving. Wii U isn't doomed, but Nintendo still needs to keep pushing if it wants to give Wii U a chance.

It was doomed conceptually from the get go. There's no amount of Mario Kart or Mario or Smash games that would save it, those just bring in Nintendo fans.

There is no market for a "casual" system, Nintendo just hit the jackpot once in a limited window of oppurtunity, the bubble had already burst before 2012 as the Wii was falling off the face of the planet in terms of popularity. People were already losing interest in a console primarily driven by mini-game experiences 

You either make a console that is basically a Playstation 4 or you can't have success with the way the industry is now.

Consoles are for big screen, big budget types of experiences. Smaller, quirkier, more accessible types of arcadey games are being overserved by the mobile market. Anyone in the middle is screwed. Unfortunately for Nintendo they're right smack in the middle. It's not just Nintendo either, Sony probably won't find a ton of success with LittleBigPlanet 3 either, just like Puppeteer and Tearaway flopped. People want things like Destiny if they're buying a console. 

PS4 is doing rather poorly itself. It just happens to be doing the 2nd best out of a bunch of consoles that are doing poorly.

Yeah tracking as the 2nd best selling console of all time after 10 months, its doing sooo poor.

Well it didn't have the burden of a 600 dollar price tag and second rate versions of multiplats to deal with.

Whatever the reason may be, it still takes a whole lot of spinning to try and say that the PS4 is doing poorly. It isn't, at all. Shipping 9.5 million consoles in 8 months is massive.

It only sold 117K last week, that is fairly poor. It's also selling behind the 3DS which is selling poorly.

Considering the data we got recently (PS4 shipments and Germany sales numbers), we can easily assume that that number is lower than the actual number, my guess is something like 15k lower or something.

The most important thing though is, and I can't believe that people still refuse to understand this, that the PS4 is in its first year and for the first year those sales are absolutely great, period. Sales are going to be considrably up in the next years.

Exactly. Its doing well no matter what anyone may say.