The actor has to have some degree of craft, along with the talent. No one tries to laugh except bad actors. No one tries to cry except bad actors. How a character hides his feelings tells us who he is. Most people don't know that, and most actors don't do that. Therefore, there are a lot of actors who put me to sleep, that are considered good actors, but they're predictable and boring. I know how the scene is going to end before it ends.
Any good director creates a playground. That's what they do. They hire the right actor, open the door and let them play because stuff will happen, right then and there. The audience wants to believe that what's going on is happening for the first time, ever. That's what acting is. That's what good scene writing is.