Same rules apply to writing essays as to giving presentations.
Say what you are going to say, say it, and then say what you said.
My grandma, a high school English teacher, drilled that into my dad’s brain, who in turn drilled it into me. It works so well.
But it’s it effective or necessary? Does it help with understanding or something?
yes. the brain is not like a computer. data isn’t just “there” or “not there”.
Data in the brain has a certain strength, and by saying things multiple times, you can improve that strength.
In my experience it helps a lot.
When you give a talk, telling the audience what you’re going to cover and what themes you will explore helps get people engaged, and ready to hear what you have to say.
During the main body of the talk the audience respond better when they know what the “point” is going to be, rather than wondering “where the hell is this going?” - Given you’ve told them what the conclusion will be, they can see your information building towards it as you deliver the talk, and so are “with” you on the journey.
Then at the end you can have a chance to reinforce key points, let people know what thet can apply themselves in their own lives or work - “If there’s one single thing to remember from today, it should be this”
Preparation and repetition help so much with engagement and successfully transferring information, and that’s true in the written medium too.
creation - existence - deletion
I always thought the idea of “say what you said” was a dumbed down version of the real purpose of a conclusion. Sure you can summarize, but a concluding section is the place for a lot of other things, like acknowledging or suggesting unresolved questions/need for additional research, placing a quote or anecdote that contextualizes your findings, or a call to action depending on the style of the piece.
“conclusion paragraph” is just another name for a TL;DR
most people don’t have the time to read the actual paper; just put the essential information into the abstract.
similar to ending: sum it up in 1-2 sentences, say bye and that’s it.