In your experience, what is required to make sex "great"?

Is it multiple orgasms? A true emotional connection? Pushing boundaries?

For me, the best sex involves love and occurs when both parties are truly comfortable with themselves and each other and truly present in the moment. When both partners are expressing their love for each other through actions intended to satisfy the deepest desires of their partner and are completely focused on each other, the result is unforgettable. What is it for you?