The rate of speed at which you speak, in terms of words per minute, has a significant impact not only on your listeners comprehension, but their perception, retention and attentiveness as well.
In addition, the use of pauses as you speak is a powerful tool. You will notice that when you pause your speech, people will lean forward in anticipation of what you are about to say.
Speaking Slowly is Common Advice
I’ve been through a number of speaking classes, groups and seminars, including Toastmasters, Dale Carnegie, etc. As anecdotal is this may be, I cannot remember having gone through a program of any sort and not heard the suggestion made of not rushing through a speech or presentation.
Follow The Leader
There is an often quoted, albeit un-findable “study” performed on the speaking rate of industry leaders, U.S. presidents, world leaders, etc. The contention is that highly influential individuals speak at a slower rate than others. The average number of words per minute spoken in an audio book, for example, is one hundred and fifty. Next time you watch a past (recorded) presidential speech, count the number of words spoken per minute. These people speak at a rate that is half that of what you’d normally expect to hear.
Phonetic Perception
Did you say Bring It or Wing It? Speaking more slowly improves phonetic perception. The ability for your listener to distinguish between closely related phonetic sounds improves. Ref: Some effects of speaking rate on the production of /b/ and /w/
What? What?
According to the National Center for Health Statistics, 8.6% of the population is hard of hearing. Many of these individuals suffer from high frequency hearing loss. the problem is not so much volume as it is the understanding of consonants. Speaking loudly increases the volume of the vowels as they are spoken from the mouth and throat. Consonants, on the other hand, tend to be formed through use of your tongue, teeth and lips. Speaking slowly stretches out consonant sounds and makes them easier to understand, whereas speaking loudly is virtually no help at all.
The Pause: Silence Speaks Louder than Words
Pausing in between words and sentences as you speak benefits both you and your audience. On your side, a pause gives you time to breath, time to think about what you’re going to say next, and (importantly) time to observe your audience and digest any feedback that may be coming in (either verbal or visual).
A brief pause gives those in your audience the time they need to take in what you’re saying in a way that is meaningful to them.