It does take more time to prepare 5 slides than it takes to prepare 7. More filtering, more focus, more thinking is required - as illustrated in Mark Twain's quote. The returns on your time investment are high however. The success rate and the number of questions at the end of your presentation are inversely proportional to the number of slides.
Why is less more?
Here are three good reasons.
- 1. By focussing on the essential, highly specific details requiring a higher prior knowledge of the topic are left out. Less is more.
- 2. By setting audience interest instead of audience knowledge as your goal, the number of questions is greater. Interest can be generated in fewer slides and more visually than knowledge.
- 3. As the number of slides increases, the distance increases between the title (the bull's eye in a target) and each new slide (a new ring moving away from the center). The audience is losing the main thread set by the title. Attention is divided.