Even Sony doesn't know why the PlayStation 4 is selling so well

The PlayStation 4 is selling faster than any Sony console ever, but that success actually has at least one executive worried.

PlayStation 4 has surpassed 10 million sales worldwide after just nine months on the market. That’s a huge number that puts it well ahead of the Xbox One and Wii U, which have reached around 6 million consoles sold each. Despite that big lead, Sony Worldwide Studios president Shuhei Yoshida isn’t sure how to maintain that momentum. A big reason for that fear is because Sony doesn’t really understand why the PS4 is performing so well in the first place.