I've been talking and writing a a lot recently about what I call 'narrative balance'. This is a balance of the components of prose: description, action, dialogue, other forms (e.g. letter, emails, texts) and exposition. Hopefully there is very little of the latter and prose writers should be able to show their readers, rather than merely describe, the scenes they hold in their heads.
At all times the plot must move forward. Pace and tension must be maintained. Economic writing allows these parts that make up a narrative balance to be multifunctional.
There is no formula nor theory about how these parts can or should balance. It is something that the writer knows instinctively rather in the same way that experienced artists add brushstrokes to their paintings. A touch of dialogue here, a little action there and maybe even the odd bit of telling from time to time. The latter is certainly a very advanced skill; we are told to 'show not tell'.
I've been writing seriously now for 17 years and this is something I've only recently become aware of. Now I look for it in books I read and in the work of my students. I try to assess it in my own work. I've recently defined it as a creative writing skull.