I accidentally untarred archive intended to be extracted in root directory, which among others included some files for /etc directory.
I went on to rm -rv ~/etc, but I quickly typed rm -rv /etc instead, and hit enter, while using a root account.
On mechanical typewriters the little arms that slap the steel letters onto the ink ribbon/paper could get physically jammed. QWERTY was designed to make it so that was less likely to happen by placing the keys in an order that discouraged it.
At least, that’s the way I learned it.
Source: trust me bro