For me it is not recording credentials with the assumption I would simply remember them later, while having every opportunity to archive them before eventually forgetting. Also, not keeping detailed enough notes & photos of exactly how my hardware is attached.
I tried to enroll secure boot without understanding what I’m doing. I locked myself out of the motherboard.
Also when you accidentally create a directory called ‘~’ the command
rm -r ~is not the right one…Ughh ! That one is nasty !
I feel like you can be a long time linux user and muscle memory can get you with the
rm -rf ~…