One thing I think is canon but I know via the Cattails fanfic. Hell month. Bruce's parents were killed in January and every year when December rolls around he gets tied up with Wayne Enterprises Christmas events, Wayne Foundation charity fundraisers and such that he can't avoid. Many rogues unless they come up with a holiday theme crime are less visible. So January rolls around and he feels he has been slacking off. The smarter crooks lay low or operate in come other city because the know that being caught in January comes with extra amounts of pummeling even though they don't know why.
