Microsoft may not have been expecting a huge sales week in Japan during its launch, but I'm sure they weren't expecting less than 24,000 units.
The Xbox One went on sale officially in Japan on September 4th and, according to Famitsu and IGN, the console launch was incredibly underwhelming. Titanfall led the software sales with 22,416 units sold with Kinect Sports Rivals (14,191) and Dead Rising 3 (7,330) following EA's first person shooter.
Although low sales were expected, it's safe to assume that these numbers aren't anywhere in the realm where Microsoft wanted or could have forseen.