Idempotency is the behavior of a function when executing a function at the output of a function n times leads to the same state as a function executing once. This is useful in a messaging environment, because delayed messages do not cause unexpected behavior. Although merging implies that messages will be concentrated to prevent duplication, the idempotent implies that the messaging system allows multiple transfers and duplicate messages, while maintaining that executing multiple copies of the message has the same result as executing a single message.