I think he got tired of fans complaining about the direction of the show, and being so visible and accessible to the media. Moffat seems like he enjoys more of being secluded and just able to write.
Here's the link: http://www.radiotimes.com/news/tv/2...ntly-if-he-was-in-charge-of-doctor-who-again/
Here's the link: http://www.radiotimes.com/news/tv/2...ntly-if-he-was-in-charge-of-doctor-who-again/