Why does Les teach if not for money or fame?
He does it to reach a multitude of people with the truth of God's Word, not for monetary gain or fame. The goal is that God's Word reach hearts, and God is blessing it and touching a lot of hearts.
Les explains that he does not do this for monetary gain and does not hope to be famous; fame would be the last thing he wants. Instead, his purpose is that a multitude of people might be reached with the truth of God's Word. He is encouraged because God is blessing the outreach and touching many hearts, and he wishes those who have helped financially could listen in on the phone calls and read the letters to see how God is working.