Information Security Incident Crisis Levels are based on information security breaches. A breach of one system could result in a collapse of the organization, author says. He says it’s possible to imagine a scenario where one system is so key to the organization that a breach of its data does result in Crisis 3, 2, 1, or 0, but that’s probably a stretch for the worst crisis levels. Getting to such a severe state probably requires a more comprehensive breach. So, let’s not get too carried away by extending the classification too far.”]
Source: https://taosecurity.blogspot.com/2009/06/crisis-0-game-over.html