It's basic math like I said before a movie only gets about 50% of its box office totals, so in order to be profitable it needs to make at least twice as much as its budget. Most movies will make their money back eventually even if they bomb at the box office due to pay per view and other home video sales but movies that don't make at least twice as much as their budget will loose money at first. Like this years bomb for example:
http://www.hollywoodreporter.com/news/summer-box-office-flops-tomorrowland-820498








