Konami's Shingo Mukaitoge has cornered the Wii's cute-but-ignored market with Elebits and Dewy's Adventure. He also fancies that, after the lacklustre reception both games received in his homeland, he's learned a thing or two about how the Japanese market works, believing it's all a matter of trust and consistency:
Well I've found that mysterious myself, as well, but the Japanese market tends to purchase games that already have previous versions, like franchise games, instead of original ones. Maybe that is one of the reasons. It's not a good thing though...
Don't lose too much sleep over it Shingo, pretty sure that's how it works in all four corners of this ball of dirt humanity calls home.
Konami's Wii Wizard: An Interview With Shingo Mukaitoge [Gamasutra]