What's the Point of Pep Talks?

Every type of sport or team activity I can think of uses pep talks as a way to psych up the team before a big game or competition.  Say the Troy High Basketball team is about to play their last game.  Their coach might say something along the lines of, “we’re ready for this”, “We’ve worked all season for this”, “Everyone is here for us, so don’t let them down”, and stuff like that.  But what does that really do for the players?  Even something as simple as a pep talk before a big game contains appeals.  If the coach said, “The other team has lost every game this season, so this will be easy”, he would be using a logical appeal because he used facts or statistics to motivate his team.  A coach might also use emotional appeals by saying “You know how bad it felt to lose last week!  We’re not going to let that happen again!”  This would inspire the team by stirring the emotions of the players.  Thomas Paine’s The Crisis is basically one big pep talk to the American Army.  They had been doing not so well in the war at this point, and Paine’s essay motivated them to keep fighting by using appeals like “The harder the conflict, the more glorious the triumph”, which inspires the men to fight for that glory.  Appeals can be found in almost anything that tries to persuade or motivate its audience, even things you wouldn’t expect like everyday conversations!