A speaker that I have been greatly influenced by is one of my best friends, Paul. I know that when he speaks, he speaks with a purpose. That is, he wants his listeners and viewers to think, feel, and respond by doing something. He takes responsibility when he speaks. Thus, he is very careful with what comes out of his mouth. He is also enthusiastic and alive when he speaks.
The worst speaker I have heard was the best man at some wedding. He bit more than he could chew and the stories that he was sharing were spread thin. He did not catch everyone's attention. It did not seem like he was himself. He just did not seem like he was even the best man.