Assassin's Creed Rogue is another of the games skipping its Xbox version in Japan, releasing only for PS3 (for the moment the PC version still hasn't been announced for Japan). Today Ubisoft Japan Managing Director Steve Miller, Marketing Manager Yoshitaka Tsuji and PR Specialist Ranko Fukui explained the reason during a livestream of the local Ubiday event on Nico Nico.

According to the trio Ubisoft had trouble selling Xbox 360 games in Japan, and on top of that users of Microsoft older console are now migrating to Xbox One. In order to take the decision Ubisoft looked at the sales of Watch_Dogs for Xbox 360 in the country, and since they were roughly between 3,000 and 4,000 units they decided to skip the platform for Rogue. 

Considering the precedent, it's definitely hard to argue against that point of view.