In the book Brown and Levinson (1978: 71-3) issue out that face mentions to a speaker's sense of linguistic and communal identity.
Any speech act may impose on this sense, and is thus face threatening. And speakers have schemes for lessening the threat, particularly to the hearer. That is where the implication of Politeness Principle lies. In their model, politeness is characterised as redressive action taken to counter-balance the disruptive result of face threatening acts (FTAs). In their idea, communication is glimpsed as possibly unsafe and threatening. The ...