Feeling this acutely today. I switched my home desktop from Arch to Ubuntu since there is some software in the AUR that I want to use, but the package builds are broken. Arch is a community project so, not blaming anyone except the guy that randomly decided to rebase his package on the git without telling anyone and didn't bother to find out what the dependencies are.
Anyway, got everything set up. Everything working fine. Rebooted a few times: no problem. Popped in an extra hard drive which is just for file storage for Steam games. Reboot and... nothing. Pulled the hard drive. Nothing. The operating system is now in a completely broken state. No start up messages, nothing. Not even NumLock on the keyboard works.
I have no idea what happened.