Powerful speech

The other day I was listening to a speech by a very successful businessperson and it was so powerful that I started wondering why do most of the other speeches that we come across in our lives suck.
Look at the voice graph of the speech.

One thing to notice is a distinct pattern of pauses. The speech would have fallen flat with out the pauses. The other aspect is the sharp increase in pitch at regular intervals and for a short duration of time. This points out to a need to a very precise wording that makes a point. Who said making an effective speech is easy . Towards the end of the lecture, the pattern of short but powerful statements increase , thus culminating in to a situation where the objective of the entire speech is conveyed to the audience. I think this pattern holds good for any talk, be it a motivational speech or a sales pitch /elevator pitch / anything for that matter i guess…..Don’t know whether this works for proposing to a girl though :)