Earlier quoted context omitted.
Amazon is at the other end of the spectrum: randomly breaking things so that everything has to be fault tolerant. http://www.codinghorror.com/blog/2011/04/working-with-the-ch... This only happened because nobody even asked "What happens if I press this button?"
This really needs to be more of a standard thing. I've been near (but as an engineer, never responsible for) production systems my whole career. None of these systems were as terribly maintained as the one in the linked article. Production data was isolated. Backups were done regularly. Systems were provisioned with fault tolerance in mind. Not once have I seen a full backup restore tested. Not once have I seen a net…
It turns out the emergency stop button was pushed in. Easy enough for us to fix then, but if the power had gone out at 4am it would have been quite another matter.
After that incident, we turned off the main breaker to the building weekly. It was great fun, as most of our offices were in the same building. We had complaints for the first couple of months until everyone got used to it and had installed mini UPS's for their office equipment.
We did actually have to use the generator for real a while later. Someone had driven their car into the local power substation, and it was at least a month until it was fixed. Electricity was restored through re-routing fairly quickly, but until the substation was repaired we were getting a reduced voltage that caused the UPSs to slowly drain...