The biggest problem with Mongodb is that it loses freaking data all the damn time. I never fully realized why it's so hated before taking my current job, which

The biggest problem with Mongodb is that it loses freaking data all the damn time. I never fully realized why it's so hated before taking my current job, which uses it as the primary database, distributed among a bunch of servers. There are all sorts of concurrency issues all the time. And no, write-concern:majority doesn't help.