Amazon is pretty strong on this front too, the most recent public example is the S3 outage and postmortem[1].
>Unfortunately, one of the inputs to the command was entered incorrectly and a larger set of servers was removed than intended.... We have modified this tool to remove capacity more slowly and added safeguards to prevent capacity from being removed when it will take any subsystem below its minimum required capacity level. This will prevent an incorrect input from triggering a similar event in the future.
>Unfortunately, one of the inputs to the command was entered incorrectly and a larger set of servers was removed than intended.... We have modified this tool to remove capacity more slowly and added safeguards to prevent capacity from being removed when it will take any subsystem below its minimum required capacity level. This will prevent an incorrect input from triggering a similar event in the future.
[1] https://aws.amazon.com/message/41926/