From the lazy slob, to the person who always eats fish for lunch, there's always one colleague who tends to get on everybody's nerves.
But spare a thought for these frustrated bosses, who have undoubtedly come across some of the very worst employees the working world has to offer.
According to Daily Mail, the employers revealed how they have had to contend with employees who were rude, reckless - and more than happy to break the rules. Some even told of how they had caught colleagues breaking the law while in the office.
They were responding to an AskReddit thread from a user who asked: "Bosses and managers, what was your worst employee like?"
One user shared a horrifying story about an angry employee. "[He] got mad and masturbated in front of the entire store," he wrote.