I have a few examples
Star Wars - why start off at episode 4 when really you could of just started with episode 1 first. The big mistake here is you start off on episode 4 and any characters that you kill off in future episodes and they show up in the first 3 episodes, its gonna make those episodes pointless to watch since you already know what's going to happened to those characters in the future episodes. Not a bad series though it's just it would of been better if they went in order or maybe I'm missing something here.
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I will go way off of the deep end here on this. Having once been a student of ancient literature, notably Latin and Greek, something that's part of the tradition of ancient epics like The Odyssey or the Aeneid, is to begin in the middle, "In media res". The length of the story then follows with flashbacks and ultimately the final outcome. It's not a straight line, chronological sequence of events, which can be boring and shallow and reads like a history text.
It's warrior waiting for a battle, meditating on how he got there, why the war started in the first place, inserting past characters into the narrative, telling back stories, etc. The final conclusion comes at the end, usually when the war is over and the soldier eventually meets his ancestors in some mythic place like the Fields of Elysium or like a Viking in Valhalla (the hall of the slain).
If you've ever read this kind of literature, it's plain for all to see that George Lucas had exactly this in mind when he conceived his characters and plot line. The first time I saw Star Wars, I noted the similarities....Oh...this is like The Iliad, an epic war, a great voyage, monsters, epic events. Today's movies are drenched in this kind of tradition, which is thousands of years old.
Tolkien, a scholar, was also immersed in literature of this sort and it clearly comes into the LOTR universe which is drenched in allusions to northern European mythology. LOTR adapted orcs from the Anglo-Saxon Beowulf epic. Dragons, wizards and great kings come from the same tradition.
It's Achilles with a ray gun, Ulysses with a space ship, ancient plot lines and sci-fi technology.
These sort of stories are not new, but go to the roots of really ancient myth, told around the camp fire, generally with poetry and song. A big part of why they work so well is that they resonate with something we're not even conscious of but that is baked into our culture, but when we go into that dark theater, we're back into the world of monsters and demons.
Do some reading on this -
https://en.wikipedia.org/wiki/In_medias_res