In high school, where I had my first public speaking lesson, I learned that a presentation should contain an overview of the topics discussed. But I'm feeling more and more annoyed by these overviews, when I watch a presentation in an online video, I usually skip them, and when I'm physically present in a presentation, or if I'm watching one in real time, I often get obred during them, unless they're very short and to the point (3 bulletpoints or less.)
I find these overviews only useful to decide whether a presentation is interesting to me, and whether I want to wagch it. When the speaker is giving the presentation, I've already made that choice, and I just want to hear about the topic itself.
So are presentation overviews useful, and if so, why?
This isn't a software UX question, but it's still about the user's experience of a presentation, so I hope it fits here.