This is My Favorite QT Movie...But Evidently it Made a LOT Less Than Pulp Fiction

I don’t think anything went wrong with Jackie Brown. It’s a great film.
One thing that comes to mind though, that might have contributed to a slight disconnect with what fans/audiences were expecting vs. what they got is that Jackie Brown is (I think) the only film that Tarantino directly adapted from an existing work. So maybe he restrained himself a bit, made an effort at cohering to the original mood supplied by the novel, and that energy came through in the final product?
Because me personally, I feel like this is his most calm, most plaintive film. And that’s what I love about it. A good slow burn, and not hyper violent (though I really don’t mind his ridiculous excessive use of graphic violence because said violence always seems to border on the realms of comical rather than morbidity).
And yeah, the acting/casting was great all around.
This film is super re-watchable, it just isn’t for everybody (in my humble opinion).
Also, it is the Tarantino film that I recommend to people who may not like his other movies.

It’s an oddity because it’s what you’d expect as a director’s final film, not his second. It’s more slow and thoughtful and doesn’t have the manic rebel energy of the rest of his ouvre. It also stands out as being his only film adapted from someone else’s material.

I like it fine, but I go to Tarantino to see a crazy magpie genius taking me on a wild ride of transgressive language and violence, and breaking all of the storytelling rules while still totally absorbing me with unique characters spouting endlessly quotable dialogue.

Jackie Brown is an unusually conservative work from a born anarchist.

According to Wikipedia, it made $74.7m at the box office against a budget of $12m. So it wasn't a failure.

Of course, it was no Pulp Fiction. ($213.9 against an $8.5m budget), but Pulp Fiction was a rare, zeitgeist-defining pop culture phenomenon that must have massively outdone expectations. I doubt anything Tarantino followed Pulp Fiction with would have captured audiences in quite the same way. He didn't have a film that outdid Pulp Fiction at the box office until Inglourious Basterds.

And in terms of box office against budget, Jackie Brown was no more of a failure than The Hateful Eight or Once Upon a Time in Hollywood (both of which made approximately three to four times their budget back). And, of course, Grind House / Death Proof was an outright failure, that probably didn't break even after you factor in marketing.

Jackie Brown clearly didn't meet expectations, especially not Tarantino's own, which is why he's never done anything quite like it again. You're right, I think: it changed him a bit. I think had it not been perceived as a failure against the behemoth that was Pulp Fiction, he may have made another Elmore Leonard adaptation -- he talked at the time about wanting to make another one, but then again Tarantino talks a lot about projects he'd like to make that never materialise. He may not have leaned so heavily into action / genre films. Who knows?

Anyway, it's certainly one of his best films -- and at this distance that's all that really matters.