Why is there always maintenance?

It’s been going on and off for a few days now. I was also requested to change my password, which meant I couldn’t get my account back for a few days. That aside, is there a reason for this constant maintenace periods? My brother, who is in the next room can still log in and play, but I can’t. Is there any solutions?
EDIT: I believe it’s fixed now. I’m back online talking to my friends! Didn’t really do anything, but I guess I just had to wait it out. Thanks for anyone that commented.