If I'm a developer, I'm not choosing between Japan and the rest of the world just like I'm not choosing between France and the rest of the world.
I'm just making a game that people want to play and selling it globally, including in Japan which is the 2nd biggest console market. The games which are successful in Japan tend to be popular everywhere, we can see that in the top 30.
People buy a game for the game, not the publisher. A game doesn't sell just because it has Nintendo's name on it. The possibility is there for third parties.