Consider your own life. Consider how it flows, how it moves. Consider what it would look like if it were a story, a movie -- what part would you play? Would you be the hero, would everything center around you and your struggles to find... love... money...to defeat the main foil in your life?
Or, if there was a movie that you were in... would you be simply a servant? One who aids others in their lives, one who runs around and make sure things happen? Would you be R2-D2, always there, always getting things fixed?
You know... Luke Skywalker was a hero -- but he also had Darth Vader. You don't have a Darth Vader in your life... unless you've had someone try to kill you, you don't even have a Greedo to your Han Solo. And you know what -- that's fine. You don't have to be the hero of your own story -- God didn't necessarily put to here to have you be the hero, the focus of everyone's attention.
He put you here to serve. But that's okay - R2D2 is awesome.