If you guys mean the lock that has a link to automatically unlock it for suspicious activity, that's usually caused by logging in via the web page or in game from a different IP address. It's an auto safety measure to prevent account theft. I always used to get it when I visited friends to LAN with WoW. First and last name + secret question will unlock it. I'm not sure if anything else like failed logins etc trips the lock but I would assume that they could too. Shouldn't have anything to do with the banwave but it could mean someone has your login info and got thwarted by the lock.