Yes, and I have actually clarified that on a couple occasions but people still want to throw around "as long as they're profitable", without realizing that if hardware gets too low it means their software won't have a large enough install base to sell to which will cause them to no longer be profitable. At what point can Nintendo hardware no longer support their software?

Right now 3DS clearly show that at 50 million units sold, their 1st party franchises have a large enough userbase to sell very strong numbers on.

Pokemon X/Y-13 million

Mario Kart 7-10 million

Mario 3D Land-10 million

New Super Mario 2-8 million

Pokemon OR/AS-8 million

Animal Crossing-8 million

Smash Bros-6 million

Luigi's Mansion-4 million

Tomodachi Life-4 million

Ocarina of Time 3D-4 million

Nintendogs+Cats-3 million

Link Between Worlds-3 million

Paper Mario-2 million

Mario & Luigi-2 million

DKC Returns 3D-2 million

Fire Emblem-2 million

Kirby-1 million

Mario Party-1 million

Kid Icarus-1 million

Pokemon Mysery Dungeon-1 million

Pokemon Rumble-1 million

Yoshi's New Island-1 million

Now let's say, the next handheld sells only 20 million, would that be a large enough install base for these titles to sell high numbers? Ya the real big hitters would still be multimillion sellers but overall Nintendo wouldn't be making nearly as much money from hardware/software and would likely need to downsize then have to scale back the number of games released which would then lead to less system selling software which then leads to hardware sales continuing to decline which then leads to less profits and the cycle would continue to repeat until they are no longer able to operate.

So I agree with u that 50 million or so should be big enough of an install base for Nintendo's unified devices next-gen to have strong software sales and post strong profits.

Nothing that u wrote applies to this thread at all, this is not a Nintendo is doomed or Nintendo should go 3rd party thread, it's just a topic I found interesting, what is the minimum amount of hardware Nintendo can sell in order to maintain strong 1st party software sales and post profits?

It really depends on software attachment. If you look at Wii U for instance, it has just over a 9 million install base, yet there are 2 games creeping toward 5 million in sales and a few passing the 3 million mark, not to mention a few more million sellers. The one thing Nintendo does have total relevancy on is quality software and IP, and that will never change. As long as their bread and butter handheld division stays strong (30 million plus), then I think Nintendo can easily survive on as little as 12-15 million home console sold.

Yeah I think you're pretty spot on there especially when looking at those hardware totals. 50 million is a good ball park. 

I remember reading the Console Wars book and Tom Kalinske at Sega was saying that they never worried about making money on the hardware, they just sold it at cost because with a userbase of around 30 million they were able to make money pretty easily. 

Now home consoles have higher software attach rates than handhelds and that was in the 90s too, but it does kinda illustrate you don't neccessarily need a monstrous userbase to make decent money if you're smart about it. 

If Nintendo can get 50-55 million handhelds + 15 million home variants with both devices sharing the same software, that should be quite profitable for them. If they can make Amiibo a consistent seller for them too, that's another revenue source on top of just games. 

The unified platform approach really does make a lot of sense for them. If the home version doesn't sell so great, it doesn't really impact them so much, high profile (and probably expensive to make) games are not stuck on a very low userbase, they're not stuck with dead inventory on a console (can quickly divert the processors/RAM meant for the console to handhelds if they use the same components), and they're just not burdened with the consant "well what are we going to do with the GameCube/Wii U" dilemmas that plagued them when a console isn't super successful. 

Wow..  3ds will easily do 80 million by itself and Wiiu likely around 25 million.