Public speaking is about charisma, and charisma is about being authentic. Being authentic is being yourself, and being yourself comes from focusing on the journey, not the goal.
(I am already dying inside.) It is typical coach talk.
What makes it even better is the fact that it is a deep scientific truth! Let me explain it to you!
Starting from the end: focusing on the goal means pursuing the activity from an autotelic point of view, where the activity is being done for the sole purpose of doing it.
Forgetting about the goal turns off your analytical/judgemental part and focuses all your brain power on the activity.
Then, according to physics, the more focused energy you put into something, the better results it yields.
Losing yourself in the activity leaves you with your most basic, most energetically efficient state of mind, called authenticity.
That, in turn, focuses on the most energetically efficient ways to gain attention — and this is where charisma is born.
Resulting in a great speech!