Everyone has his or her own personal rhythm, the tempo at which he or she thinks and functions and is most comfortable.
People generally have a difficult time with people whose rhythms are different from their own. Think about it — if you speak quickly, do you find yourself getting impatient with someone who speaks at a much slower pace?
Do you perceive them as dull, perhaps not too bright?
On the other hand, if you have a more laid-back rhythm to your speech, do you find people who speak quickly annoying and difficult to deal with?
This is very common. People can grasp your message much more effectively if it is delivered in a rhythm that matches their own.
Remember that your goal is communication. Therefore, try to follow your prospect’s rhythm. Match your timing and tempo to theirs. You can even try and match their volume. This will aid in their ability to hear and understand you. If you find this to be difficult, try practicing with a colleague or friend.