It does happen in other games. But it has to be serious loss of time. Some games used to have an hour maintenance scheduled every day. If down time in a month eclipses 72 hours(arbitrary number) then you might expect something. If they go the more WoW clone model. But expect something like everyone gets the free panda minion we couldn't get. And no it doesn't matter if its 42 hours over a month and it is the 2 hours you can play every day. They do not guarantee live 24 hour servers.