The following is an excerpt from an Iwata Asks feature between Iwata and Miyamoto on the Wii U...

"Shortly after the Wii console was released, people in the gaming media and game enthusiasts started recognising the Wii console as a casual machine aimed toward families, and placed game consoles by Microsoft and Sony in a very similar light with each other, saying these are machines aimed towards those who passionately play games. It was a categorisation between games that were aimed towards core, and casual. I certainly do not think that Wii was able to cater to every gamer's needs, so that's also something I wanted to resolve. The general public's impression that Nintendo was casual grew as time went by." - Iwata

"One of the key reasons that such things as the core and the casual exist today is that we decided not to adopt HD on the Wii console. Of course, besides that there are things like issues with the controller and the challenges that it brings, network functionalities and many other things, but I think HD was the biggest factor that everyone was able to clearly understand the difference." - Miyamoto

"The barrier that separated the two genres [core and casual] was only something psychological, just an impression that people had about them. For example, The Legend of Zelda games were something geared towards the toughest audience, and it has been so from the beginning. So it's not like at Nintendo we don't have it in us." - Iwata

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