I’ve got some good news for you: you are a powerful speaker. 

This  means that you are brilliant. You have incredible ideas. Every question  that you ask is insightful. You have compelling ideas to contribute,  important businesses and organizations to build, and provocative  questions to share. However, there is the possibility that the way you  speak fails to command your power when you are sharing the importance of  public speaking. You may equivocate, apologize and look away as you  speak. What you are doing is subtly undermining yourself with your words  and body language. 

As a result, your ideas do not have the impact they  could.