I've been surprised by how often movies with similar themes end up being released at roughly the same time by Hollywood studios. Since it takes several months to shoot a movie this means that somewhere along the line some Hollywood exec hears about a rival studio producing a movie and decides to produce a movie with a similar theme. Some examples that come to mind are
I'm sure there are dozens of examples like this from across the years. What I wonder is whether I'm right that Hollywood execs just have a "follow the leader" mentality and decide that if a competitor is shooting a disaster movie for summer of next year that sounds like a hit then they need to shoot one as well. Or is there some more sophisticated reasoning at work?