NOW I finally understand the purpose of the conductor at the symphony. He's there to give us some action to watch. Think about it, the faces of the musicians are so stoic, and you don't need to watch them anyway because you just want to hear the music, right? I mean if you notice, no matter the tone of the music they're playing, whether it be happy, sad, upbeat, suspenseful, they have the same expressionless faces!
So, while we listen to the music, the conductor is just there to give us more expressions to see. I swear, I was at the symphony last night and the conductor had more facial expressions that fit with the music than any of the musicians. And this I saw WITH his back to us of course! But you could just see how much he was getting into the music and when I was able to see his profile, it had more expression than the musicians.
Because why else does the conductor exist? After all that practice, would the musicians really NOT know when to play what???