The ephemeral nature of a voice call is not only an advantage for questionable activities. You can defuse a potential conflict by voice call because the medium

The ephemeral nature of a voice call is not only an advantage for questionable activities. You can defuse a potential conflict by voice call because the medium allows airing of issues in a more candid fashion, and allows more rapid convergence onto common ground compared to text based communication. I think that bad news is best communicated along channels that allow some kind of non-verbal perception (on a phone call largely by judging the nature and length of the silences). Face to face is best, but synchronous voice communication is a second best.