the Power of Three
We believe the human mind was designed to find threes satisfying, and to feel that something presented in threes has made its case.
Two of something seems in opposition; three of something seems a completion.
There can be threes in terms of three modifiers for a noun, the tripartite story(open,body,conclude), or three phrases or examples.
All of these things are tremendously important things to consider as we lay out that speech and begin to organize our material within it.