League doesn't want me to exit?

I was getting ready to go to bed and I clicked the X button in the top right corner and it popped up a message that said "if you exit the game now, you'll reieve a time penalty that will either stop you or your team from entering a matchmade game! If you are in a League series, dodging will end your series if this is the determining loss. Are you sure you want to leave?" why does it say that?