When the Wii U was first announced, it was met not with reactions of joy and anticipation, but questions and concerns.
The reasons for this were numerous, but they largely focused around the Gamepad. What was it? What functionalities did it have? How did it feel to hold? Was it more for gimmicks, or for playing games on? These and more spread throughout the internet like wildfire, and satisfactory answers were not forthcoming. This made it a hard sell for many, and a hard console to make games for. Eventually, it seems, most devs just chose to abandon the gamepad, and later the console itself. At the end of its life, the Wii U had sold a measly 13 million consoles, coming in as the worst-selling Nintendo console of all time.
Enter the Nintendo Switch.