Studios tend to dump their crappiest-looking movies during particular times of the year.
The cinematic version of the Friday Night Death Slot, the Dump Months are certain months of the year that are viewed as, effectively, cinematic landfills where little of value can be found at the box office. Disastrous productions that the studio wants to get behind them as quickly as possible with minimal fallout, low-budget genre fare that can't hang with the big boys of summer, star vehicles for fading stars, B-grade thrillers and comedies that aren't quite bad enough to be shuffled into the Direct-to-Video netherrealm, films that the studio's been sitting on for years and are only getting released theatrically a) out of contractual obligation or b) because somebody involved with the film has dirt on a studio executive, all of this goes to the dump months to be forgotten about by the time they come out on DVD and start airing late at night on cable three months later. In the US, at least, it is the months of January, February and September that are most often seen as dump months.
- September is obvious -- it's the end of the Summer Blockbuster season and the kiddies are back in school, but the holiday season (Thanksgiving, Christmas and Oscars) where family films and arthouse fare thrive is still months away, while the studios are saving their biggest horror pictures for October. Plus, many families use Labor Day weekend (the big holiday during this month) for vacations, barbeques and watching football, keeping them away from the theaters.
- January and February, meanwhile, are past the cutoff date for Academy Award nominations but before the actual ceremony, meaning that all the big "prestige" pictures have been released and are expanding into wider markets as part of the Oscar campaign. Plus, winter in the US is a time when several large cities at once, especially in Northern states, can easily be shut down by a large snowstorm, preventing people in those cities from getting out of their house to go to the movies. Studios don't want to cannibalize their own films, especially their best films (or at least, their most Oscar-oriented films), nor do they want to risk freak weather events killing their big movies' box office prospects, so they stock the new release schedule mostly with cheaply-produced crap for two months.
Fictional examples and discussions:
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