The Nintendo Switch is presently Nintendo’s fastest selling system of all time, also managing to pull in a tremendous amount of software sales, and forecast to sell 20 million more units in just its second year on the market. The incredible thing is that it follows right on the heels of the Wii U, Nintendo’s worst mainstream hardware bomb of all time. A console that followed on the 100 million selling Wii, and ended up selling less than 14 million over the course of four years.

How was this turnaround even achieved? It’s incredible, after all. The Switch managed to sell more in nine months than the Wii U did ever. How did that happen? Speaking at the Geekwire Summit (via Ars Technica), Nintendo of America President Reggie Fils-Aime suggested that it was because Nintendo learned what works and what doesn’t from the Wii U, even going so far to suggest that the Switch wouldn’t exist without the Wii U having come first.

“Without Wii U, we would not have the Nintendo Switch, in terms of what we learned and, importantly, what we heard from our consumers. They told us, ‘I want to play with this gamepad on the Wii U, but as soon as I get more than 30 feet away, it disconnects.’ The core concept of taking it any time, that was compelling,” he said.

It does seem like the Wii U was in a way trying to achieve the Switch concept a bit too early, back when the tech didn’t exist. It also seems like its failures allowed Nintendo to figure out what doesn’t work, and address that, while figuring out what does, and refine that. Whatever it was, it turned out to work— now let’s just hope they don’t need a Wii U style wake up call again to turn out their next big hit.