Know when normal becomes distracting
A 2024 study tested public speeches with different disfluency rates and found that five disfluencies per minute did not hurt perceived effectiveness, while high rates around twelve per minute did. Toastmasters also notes that spontaneous speech is naturally disfluent, especially when a topic is difficult or the speaker is nervous.
That makes the useful coaching target practical: reduce repetitive fillers and habit phrases without trying to erase every human pause.
Sources: Journal of Applied Behavior Analysis study on disfluencies and Toastmasters on the science of disfluencies.