This happened in 2014, but it was such a colossal disaster, I feel the need to share it here. At that time, I worked as a presales consultant for a large OEM and my clients were predominantly fortune 50.
One of them had just changed their IT management in the Northeast and the new top dog wanted to do a catastrophe recovery test. His idea was was to completely power down one of the DC's out route 78 in NJ. I and every other OEM consultant advised him against it.
We argued: you are attached to two grids, you have enough battery for 12 hours, and enough on site stored diesel for your generators for a week, your DC is specifically designed not to ever have to power down. His response was: "That is exactly why we need to see it come up from a complete power down!".
The Thursday before the Friday night power down, I went through that DC with one of my storage SE and a server SE. I wasn't worried about the servers. I asked the storage SE his thoughts - his reply was: we just did a complete refresh and our oldest cabinet is 2 years old, we shouldn't lose too many spindles. I looked over too the mainframe corner and asked him: "those are the same cabinets I saw here in 2005, aren't they?". He replied: "yep, they just swap in new drives as they fail".
They went ahead with the power down. We lost two raids in forty+ storage systems (~6000 hdd) due to multiple spindle spin up failures. 24 of 32 mainframe cabinets lost all arrays due to spin up failure - shutdown a spinner that has been spinning for 10 years and the odds are against you.
Two weeks later I met the new Northeast IT director.
What prompted this memory is reading of members here spinning down disks at night to save energy. It just tweaks a nerve in me. I love solid state, almost.
Don't talk to me about tape, in any format.