Why don't they all go mobile? Because it doesn't work for all games. You can only put so much on the screen until the game is crap. Other companies have tried and failed with putting big games on mobile. Mobile is just not going to be a place for big games that give you full control of what you are doing.

Nobody should go full mobile

EA should go full mobile then hopefully they will die a slow and horrible death like Zynga.

I hope somebody makes a thread about Sony or Microsoft going third party or full mobile, I'm tired of people who wants Nintendo stop making hardware or who wants them to dissapear completely...

It wouldn't work. Sony and Microsoft games are much better suited to consoles, while I think many Nintendo games are as well suited to smartphones as they are to consoles.

Funny thing Sony and Microsoft makes smartphones, Nintendo doesn't and there are plenty of franchises Sony and Microsoft could put on mobile devices. And anyway like somebody else said, if you want to play a Nintendo game go and buy their hardware, the 2DS is way cheaper than a good smartphone.

It's clear that you haven't played many Nintendo games. Outside of a few turn based rpgs and stuff like animal crossing most flat out wouldn't work. IPs would have to be dumbed down or given a mobile centric spin like pokemon go to work and that's not something I want to see from Zelda, metroid, xenoblade splatoon and all the rest 

Smash, Donkey Kong, Splatoon, 3D Mario, and 3D Zelda would be godawful on mobile devices. I don't know if you noticed, but those are several of Nintendo's biggest franchises. Even smaller ones, like 3D Metroid, Luigi's Mansion, and most of the Mario sports games would similarly suffer. And while it could work for stuff like Yoshi, Kirby, and 2D Mario, Zelda, and Metroid, it wouldn't really be the optimal way to play. The only games that translate really well would be Fire Emblem (which still isn't that huge), Animal Crossing (which is only one series), Tomodatchi Life (which is only one game), and maybe, MAYBE, the Mario RPGs, which honestly aren't that big either, and maybe Pikmin (coming from someone who hasn't really played much of it).

The concept of expanding, why dont people understand it?

Nah. Just go third party but releasing games for mobiles and also for PS4, XOne and PC.