We have a lot of automation/tools to prevent incidents when mitigation is straightforward (e.g. roll back a bad flag, quarantine unusual traffic patterns), which means that when something does go wrong it's often a new failure mode that needs custom, specialized mitigation.
As Douglas Adams says, "The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at or repair."
As Douglas Adams says, "The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at or repair."