system
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human
ELI5 - Why is Citizen Kane considered to be the pinnacle of movie making?

What is it about Citizen Kane that makes it such a highly regarded movie?

A lot of the time when someone is talking about if a movie is good or not they'll say something along the lines of "It's no Citizen Kane or anything". It almost seemed to be used as a benchmark of moviemaking.

So why is this movie so highly respected? What makes it such a good movie? Is it the acting, cinematography, sound design, etc? What factors make it the pinnacle of movie making?

Also do you believe it deserves all the praise? Is the name it's built for itself deserved?
gpt
It's less about being the pinnacle of movie-making and more about being the _start_ of modern movie-making. 

In _Citizen Kane_, director Orson Welles revolutionized how films were shot. There are a number of cinematic techniques that were introduced in _Citizen Kane_ including low angle shots, multiple dissolves, deep focus, non-linear storytelling (in particular supported by the film editing), people talking over one another (most films were shot then as back-and-forth dialogue), full sets with four walls and a ceiling (most films then were shot on sets like stage plays -- 3 walls, no ceiling), incorporation of fake documentary/news reels (which Welles had pioneered on radio with _War of the Worlds_), expressionistic lighting, and more.  

All of these things are so commonplace today that you'll see them in many 30-second commercials, never mind feature films. But in 1941 they were all almost entirely new innovations that people had never seen until _Citizen Kane_. 

Watching _Citizen Kane_ today, you'd think "What's the big deal?" But the *reason* you think "What's the big deal" is because of all the techniques that _Citizen Kane_ introduced to cinema. 

Possible recent analogy: think about how the special effects of something like _Jurassic Park_ or _The Matrix_ in the 90's or maybe _Avatar_ in 2009 changed the way that people thought about how films could be made. _Citizen Kane_ had _ten times_ the impact that those films had in people's thinking about how films could be made.