Oh, you mean some of their most successful consoles ever?
Also the Gamecube was stronger than the PS2 yet we all know how that turned out.
The DS and Wii succeeded based on fads that are no longer new, fresh, and exciting. Touch control especially is sort of becoming standard.
And the Gamecube failed because
NINTENDO THOUGHT IT WOULD BE A GOOD IDEA TO MAKE THEIR OWN BLOODY DISC FORMAT THAT COULD ONLY HOLD 1GB OF DATA.
And that was equally hard for third parties to work with. PS2 was less powerful, but it was close enough to the GC and at the end of the day, it went with the DVD standard disc format that could hold 4GB.
Stop oversimplifying everything. Just because something worked for them one time or didn't one time, doesn't mean it will come out the same again.
The general reason Nintendo's consoles fail is because they have an awful habit of being different for the sake of being different. Using dated architecture because it's different, or making up an objectively inferior disc format. There is always something.
They just need to make sure the NX doesn't have that something. That one catch.
You really can't defend this practice. It's like going into an exam, failing it on purpose, and then claiming "oh, I failed because I knew everyone else would pass. Failing makes me unique and different, and therefore better than everyone else". That's literally Nintendo's line of logic with these things (according to their PR speak), and it needs to stop.