Some people were just born public speakers. Others are terrible at it, they suffer from stage fright and should just avoid talking to crowds altogether.
That way of thinking is very convenient but, unfortunately (or fortunately), not supported by facts.
Most of us have attended some presentations or watched TED talks that left us with a feeling: “Wow, this guy knows how to get the audience’s attention! I’m so jealous, I wish I was like him/her”. What if I told you that this guy isn’t “a natural”, but has been working very hard to sound so? What if I told you that you can give talks that people would enjoy listening to?