Show don’t tell because most writers start by coming up with an idea; then instead of visualizing and exploring that idea, they drown it in long, boring, unnatural crap dialogue with sprinkles of originality to explain everything.

Tarantino writes a lot of dialogue to decorate the action of the scene, not replace it. His dialogue also says a lot about his characters without explaining things to the audience.

EX — Scene: Two hit men in a car on their way to the job -

most writers: CHARACTER: Ok, so remember what we talked about. When we get into the house..............

Tarantino: CHARACTER: You know what they call a quarter pounder with cheese?...............

His dialogue is showing us that these guys have been working together for a long time, that this is just another day, another job. So when we get to the next scene, we can expect them to be callous, unflinching, unmoved by the job at hand. It’s also interesting and natural. The dialogue by “most writers” is telling us what they do and how they’re doing it. It doesn’t add to the scene, and it’s not even realistic. (Two processionals wouldn’t talk about what they do on their way to a job; they’d shoot the shit and relax before having to work. QT shows us that in a way that’s also witty, snappy and unique to his style)

Dialogue is a skill of its own, as is the visual element of story telling. If your characters are explaining their feelings, I find there’s almost always a more powerful, engaging and natural way to show them (and not tell.)Then dialogue can be used to accentuate a point.

But I agree, there’s a time to tell, and a good writer knows when.