Speakers can open their presentation many different ways. Why do most non-professional speakers begin their speech with, "Ah, I am so-in-so, ah...um"?

Beginning your speech with filler words such as "ah" or "um" immediately tells your audience that you are an untrained speaker. In a flash, you've lost credibility as a speaker—or worse, as an expert in your field—and your audience has taken a mental exit. You now might as well be talking to an empty room.

Why do speakers self-sabotage their speeches by beginning this way? It's simple: it's because...