Each actor who enters the profession carries with him from childhood a starvation for approbation. As he grows older, he finds that acting is a socially acceptable form of doing something in hope of getting the kind of approval that he missed in his childhood. A director understands that to an actor praise is like food. The actor cannot live without it, cannot flourish without it. A director must discipline himself to praise ceaselessly.more from "A Sense of Direction"
It is not necessary for the actor to have done something extraordinary in order to be praised. General praise, in comments such as "you're doing nicely" or "This scene is coming along" or "It's a pleasure to work with you" doesn't have to apply to any specific achievement, but it lifts the actor's spirit and causes him to flourish. He feels his flower is blooming. He feels his life is healthy. He feels as though the sun is shining if a director, who is, after all, the authority figure, is in favor of him.
It's important for female directors to ensure that they establish themselves as authority figures first, in order for this to work. My daughter has suggested to me that I'm too open, and therefore too vulnerable in my approach to actors, and set myself up for disrespect and grief from those with an inclination to exploit any signs of "feminine" weakness.