[bluGill]

30 years ago companies were rebooting their mainframes twice a year just to make sure. Before doing that companies were burned because the mainframe went down accidentally (backup generator broke during a power outage) and they couldn't get it to start because someone changed a setting at runtime but didn't save the setting to the boot scripts - then that person retired or found a new job. By rebooting twice a year they were able to ensure the someone remembered what setting was changed when the system failed to start.

[datadrivenangel]

Chaos Engineering!

Untested emergency plans are not a guarantee that the plans will work.

[NikkiA]

One of the things that I loved about ISO9001, sure, it made every sysadmin action something that made police paperwork look 'light', but it ensured you didn't hit this kind of thing, or if you did, it was an instant gross negligence dismissal on whoever stopped documenting or following the documented procedural protocol.