NX just needs to be profitable at a reasonable level for Nintendo.
It doesn't need to sell 100 million units (for the console variant anyway).
Even 35 million ... I would consider at this point to be a fair success given how the Wii U finished and 40 million to be something Nintendo would be quite happy with. I think if you gaurunteed them right now 40 million in sales but no higher for the console NX, they would take that and run.
They will make hundreds of millions of dollars every year from mobile, NX doesn't need to be the be-all, end-all, but even 35-40 million isn't a lock by any means. They need to work very hard to get to that.
Sony and MS have long headstarts too, that's problematic.







