As an example of an effective player, look at Dwayne Wade. He isn't a PG, but still knows he has to involve his teammates so he has 8 assists a game. He knows he has to get to the line and as a result has earned 11 shots from the line a game. He takes circus shots every now and then, but is shooting 48%, excellent for a guard. Best of all he knows he really doesn't have 3 point range so he only takes 2 shots a game from beyond the arc, preferring to go to the basket and earn those free throws.
That is an effective player, something he obviously had to be to get his team a title.