Speakers often forget that the human listening capacity and mental retention capacity are limited. So they can imbibe only a few key learning points in each session. Using slides makes presenters think that they can thrust as much information on the audience as they have on their slides. After all, you can have hundreds of slides in a single file ! But the human mind does not accept information that way. So speakers end up having numerous slides and make presentations that overwhelm the audience with information.
I took a minute to think about the most impactful speakers of all time. A few names popped into my mind immediately – Jesus Christ, Gandhi, Winston Churchill, Abraham Lincoln, Martin Luther King…(not in chronological order). Guess what – none of them used slides!