Wii U hardware producer Katsuya Eguchi brought out that the Wii didn’t have many multi-platform titles because the Wii Remote lacked the controls of a traditional controller. Here is what Eguchi said concerning the Wii U Pro controller:
“Adding a Pro controller may make it easier for multi-platform games to come out on the [Wii U] system. Wii remotes don’t have things like analog sticks. To make it as easy as possible to enjoy certain multiplayer experiences it was important to have that Pro controller.”
“We’re all gamers as well and we appreciate the interest of those [hardcore] gamers, and we don’t want them to feel left out, so we’re making big strides and changes in that area.”
Eguchi brings out that the Wii U Pro controller may allow multiplatform games to come over to the Wii U easier. The Wii Remote controls could of been a problem for multi-platform games, but I would also think the Wii’s power also had a factor in that.