Why is it important to smile and make eye contact with the audience? it shows that you have a sense of humor. it makes you look more attractive. it shows that you are engaged and happy to be there. it proves that you are relaxed. you don't need to smile unless you tell a joke?

    It shows that you are engaged and happy to be there

Explanation:  According to social and psychological studies, successful performance is considered if a contact of trust and mutual relationship with the auditorium is achieved. This implies a stance that reflects your confidence in yourself and you believe what you say before the auditorium. In order to achieve this, the one who is in contact with the auditorium must demonstrate this with his engagement that he is interested in transferring a certain story to the listeners and to show that he believes in it. No one will believe in the story of a lecturer, and especially he wants to relay this story to listeners if he is frowned and if he avoids eye contact. According to psychologists, avoiding contact with the eyes is a sign that something is hiding, and not that he wants something to be told with confidence. It means that the lecturer doesn't feel satisfied while transmitting the story.

If we want the auditorium to be trusted, we have to be engaged and smiling, because we give the impression that we care that the listeners believe in our story, and that we feel satisfied because we ourselves believe in it.