Justin Timberlake says he doesn't like to hear himself singing or see himself on screen.  It's too "painful."

"It's painful for me to either watch or listen to myself. But even when you're not fully satisfied
with the outcome, that's what makes you hungry. But there is
gratification in the fact that you a. make people smile, b. make people
dance, c. make people laugh or d. make people make babies."

He's setting himself up with that one, isn't he?

And J.T. also thinks acting is totally non romantic, so I guess Jessica Biel will never have to worry that he'd run away with a movie co-star.

"Acting is a totally different process than music. Music is a study in
the romanticizing of human behavior," he explained. "I have found that
acting is like the un-romanticizing, that’s not a word, it is the
opposite of the romantics of human behavior."