Why is Chekhov's Gun so Satisfying

Recently I've been reading the Expanse series by James S.A. Corey (and if you haven't I suggest you take a look at the first book, the prologue is generally enough to get you hooked).  One of the things I've noticed in his books are a very satisfying and successful use of "Chekhov's Gun" and it got me thinking about what makes them so satisfying. Chekhov's Gun is a common trope used in writing that was originally coined by Anton Chekhov.  He said that:

"Remove everything that has no relevance to the story. If you say in the first chapter that there is a rifle hanging on the wall, in the second or third chapter it absolutely must go off. If it's not going to be fired, it shouldn't be hanging there" Anton Chekhov (1)

Checkhov describes it very simplistically, if it's there, it had better do something or why did you put it there?  For example some charm a character's parents gave them in the first chapter could turn out to be a key later on.  Someone who is unaware of Chekhov's Gun will enjoy the "Aha!" moment when they realize it's real use, but what about people who are aware of it?  Those people that realize that the moment the charm is introduced, that it will have some importance later in the story?

To me the reveal is what defines a good Chekhov's Gun.  At some point during the story a problem is going to present itself.  If you can craft a story where the reader finds herself realizing the importance of some object at the same time the protagonist does, it creates a very satisfying moment.  The reader not only gets the enjoyment of solving a puzzle, but also feels a stronger tie to the protagonist who realized the same thing (the character thinks the same way I do, I can relate more to them).  The same can be applied to the antagonist.  If the reader is able to piece together something bad that the antagonist can do right before he does it, the reader get a great "that son of a bitch" moment.

Chekhov's Gun has been one of my favourite tropes and I'm looking forward to picked out more in the Expanse series.  Hopefully now you can too!

https://en.wikipedia.org/wiki/Chekhov's_gun

1. S. Shchukin, Memoirs (1911)