One of my pet peeves is when rules counteract the purpose they are supposed to serve, usually because of incompetence. Two years ago, I worked for a few months for a company where time reporting was accessed through a specific web page.

They required the password to be changed monthly, have at least 10 characters, at least one number and at least one special character. On top of that – they locked out password managers and pasting. "We need to make sure you are the one logging in and not a hacker that hacked your password manager" they explained when I asked.

Out of spite I went for "Password12!" the first month and "Password123!" the month after, at which point I received an email from the IT department explaining to me that my choice of password was endangering the corporations security.