When we see an outgoing communicator call being made in Star Trek, the caller taps his commbadge and sais, e.g. "Picard to Riker." The answer is usually instantaneous.
When we see an incoming communicator call, the commbadge beeps and we hear the hailing message, i.e. "Picard to Riker." The called (Riker in this example) then answers.
Up until the last word of the hail is spoken, the commbadge does not know whom to call. Even if it temporarily stores the hailing message, relaying it as soon as the recipient is identified, shouldn't there be a pause on the caller's side of at least the length of the hailing message before the recipient even could answer?
(I fully understand why you wouldn't want to bore the audience with this, but is there any in-universe explanation I missed?)