Metroid doesn't sell and why should they make a new IP if no-ones bother to buy it?

It'll be funny when this DKC sells less than Metroid Prime on the GC...

"Nintendo would only focus on their highest selling titles if they were to go third party, because there'd be no need to build a userbase." Isn't that what people say all the time? And yet we're watching that happening on the Wii U even while they stay a first party, and it's not working at all for them so far.