It's the holy grail of presentations training:
"Tell them what you are going to tell them; tell them; tell them what you have told them"
It's also quite possibly the biggest load of nonsense I have ever come across and the one piece of advice that, if followed, is guaranteed to make your next presentation a boring one. The simple format outlined above is great if you are a six-year-old doing show and tell at your school. It gives the little tike some basic structure to bolster their confidence and help get them through the dreaded five minutes they have to fill. If you are an adult, however, you require something more.
Repeating something three times does not make it interesting or engaging. Nor does it make it memorable (particularly when your audience has nodded off in the first ten minutes). If you want an audience engaged and interested in what you have to say then you need themes and stories rather than mindless repetition.
The ability to articulate your story or that of your company is crucial in almost every phase of business management. It works all along the business food chain: A great salesperson knows how to tell a story in which the product is the hero. A successful line manager can rally the team to extraordinary efforts through a story that shows how short-term sacrifice leads to long-term success. An effective CEO uses an emotional narrative about the company’s mission to attract investors and partners, to set lofty goals, and to inspire employees.
The "tell them what you are going to tell them" approach is a poor substitute for great storytelling. It's also a poor substitute for mediocre storytelling. Every presentation should be built on good stories and a common theme that binds them altogether. Only then are you interesting and engaging.