It is rude to withhold information.
Phil is at the police station and the police are questioning him about a robbery.
Phil wants to answer the questions.
Phil answers truthfully and tries to cooperate with the police.
Phil omits important details about the robbery so as to not incriminate himself.
The police are grateful and Phil gets a lighter sentence for his cooperation.
The police find out that Phil was involved, and he gets in more trouble for lying to the police.