A very bayesian mistake. If you know nothing about a person, then observation of a fact that he is late is an evidence that he is a kind of a person to be late.

A very bayesian mistake. If you know nothing about a person, then observation of a fact that he is late is an evidence that he is a kind of a person to be late. If you think about it, it is highly more likely to see this kind of person to be late, than to see a person who "never late" to be late. If you knew your coworker better, if you've formed your own theory about how he is likely to be late, than if he is late you'll probably assume that he faced some external force which became a cause of his lateness.