The Actor's Contract

When an actor steps out on the stage, he enters into a contract with the audience. To wit:

The actor promises that to the very best of his ability he will be the character he is playing on the stage even if it includes doing or saying things that the actor would find stupid or embarrassing to do on his own.

The audience, for it's part, promises to forget that it's the actor, and instead see the character and afterward congratulate the actor on being someone else.

If Bob goes out on stage and is Leandro, the audience will see Leandro.
If Bob goes out and is uncomfortable performing Leandro's actions, the audience will see Bob doing a bad job of playing Leandro.

Ideally, the actors vanish, and only the characters are visible.