This might be because a lot of people have no idea what the viable use cases are for all the million different new database-things there are. Because it just is

This might be because a lot of people have no idea what the viable use cases are for all the million different new database-things there are. Because it just isn't that clear unless you have used them all or are a total nerd for the design of database software. In this respect MongoDB is partly a victim of its own success - that means more people using it who aren't sure what it's for, or who are led to believe it's for something it's not really so hot at.