It's probably Nintendo's worst console to date. Not that it means it's terrible, but if you didn't like some of their previous ones, this one is probably off the table.
It lacks notable franchises (Metroid, F-Zero)
Some of it's notable releases have been of questionable quality, even among their fans (Star Fox Zero, Mario Tennis)
Smash came awfully late and wasn't even exclusive to it because of the 3DS version (which came out sooner)
3rd Party support is arguably even more lacking than previous consoles
It's launch went terrible because they were slow to get the good games out, which screwed it even more
Sometimes, it felt like even Nintendo didn't know what to do with the gamepad
Low data storage for this day and age
High cost that hasn't come down much (yes they bundle 2 games with it, which makes it a better value, but that initial price matters a lot to consumer perception, especially if they don't like the bundled games)
Honestly kind of underpowered when it released
Won't have a new Zelda game exclusive to it
I know it sounds like I'm hating on it, but if you like platformers and mario stuff in general, it has your back til you die. It does have it's own gems beyond the standard mario fare (Splatoon, Xenoblade X, Bayonetta 2, plus some eshop titles that pick up some of the slack), but they are fewer and farther between.
Not saying it's terrible, but I've been feeling a bit demoralized regarding the system lately. It doesn't have a lot of games that I truly love, especially compared to previous systems. Even the gamecube is laughing at it in terms of hardware sales. Depending on how the NX looks, Star fox Zero might end up being the last game I buy for the system, which feels sad as I wasn't exactly thrilled with it. Might get Pokken tournament later, but I'm not sure as I have a bunch of other games I plan to play this year.
Gah. I really hope the NX is better.