What makes a good speech?

Dan Pink, author of A Whole New Mind says the 3 keys to a good speech are ..."Brevity, Levity and Repetition."

Here is a video of Dan that also includes the quote above.
http://www.youtube.com/watch?v=WhKLSTBSgwI

What do you think is the key to a great speech?

Leave us a comment and share your ideas !