Sever Rollbacks can be caused by Hardware issues to Players using Hacks in-game which cause server instability and corruption. (Say Thanks Cheaters)
This corruption can only be fixed by reverting to a known good save of the server.
GW 2 for example did this on rollback - https://twitter.com/GuildWars2/statu...91711002955777
A thousand times this.
This is what happens when players use hacks to cheat in-game. The game we play is saved server side. Some idiot players decided using hacks would be a good idea. They were wrong, and have now ruined it for a lot of players. Bioware is probably still investigating the full situation. Companies will never divulge the full story until they actually HAVE the full story.
Don't blame Bioware because somebody wanted to cheat the game. You'd be suprised how many try every day.