Markets can be weird. The people who go to markets can be weird. There's just all kinds of potential weirdness.

It seems like they did a good job of getting it going again. It's a bummer that it went down, and ideally they would have a system in place to test the new hard forks before releasing them. Then these issues wouldn't happen. However, it seems that the witnesses did a good job of responding and getting things working again as quickly as they could. We're off and running again!