Outlines of a presentation is normally given in the second slide of a presentation. Why do we often see outlines of scientific presentation in slides?
Is there more to it rather than delivering audience's "expectations" that they will stay throughout your talk? For example, "oh, the presentation outlines is only 4 bullet points, this will be a quick one to see before I head off for lunch shortly."
I always provide an outline for a number of reasons.
First, it helps participants scan the slide handouts in the same way as an index.
Second, it helps align expectations with the audience, so they have the chance to leave for lunch if they don't like what they see.
Third, it helps set a "learning frame of reference". The structure of your presentation most likely reflects how you mentally structure the topics you are going to present - use that to give the audience an initial high level bird-eye view of what is going to happen. A good idea is to not only have headline such as "Personas", but maybe also have a subtitle to infer some meaning: "Personas - getting to know your users", for example.
Finally, I learned that you should always provide a brief outline when presenting at an oral exam. Quite often you are asked a question that are not entirely in context with what you are presenting at the moment and by referring to your outline, you can tell that you will get back to that question in detail once you get to the corresponding part of your presentation. This helps you keep your presentation on track and applies to a lot of other situations than exams.
A four-bullet presentation may still take one hour per bullet, so that's not the case. A slide or page counter is what is usually used for this purpose.
I think an outline is there for the same reason as introduction and conclusion are in a usual text. It sets expectations in terms of "lecturer is going to start with a case study, then discuss theory in general, after that he or she will go through all kinds of categories and finally open questions will be named". If there was no outline, one may wonder if a discussed example is a general or a specific one, if there are other ways to classify phenomena etc.
I guess that scientific/technical presentations may have outlines especially often because scientists/engineers are accustomed to follow a common thesis structure, which typically looks like "abstract > outline > introduction > background > methods > results > conclusions".
