It's rude to make people angry.
John was at work busy on some work assignment for his boss when Tim comes in.
Tim wants to talk to John.
Tim talks to John, and he points out that someone left the copy machine on.
Tim starts pestering John over and over again until he starts paying attention to Tim.
John runs to the copy machine and shuts it off to save the company the electricity.
John is now annoyed with Tim and his antics at getting attention.