You will never know enough at the time the crisis hits. Assessing why it happened may not be as productive during the storm as focusing on what to do. Assessment can come after calm has been restored. An escalating flow of events. A crisis never remains static.
Events take on a life of there own.
Intense scrutiny from the outside. Everyone from shareholders to consumer advocates wants to examine the inner workings of a web site or organization that allowed this event to occur. However, the best course never is to stick one's head in the sand. Events are out of control. This isn't our fault.