Well, amongst the many aphorisms of the movie biz is "show, don't tell". Using Blues Bros. as an example, their meeting up with Rufus after their meeting the Penguin gave you enough establishing background on Jake & Elwood without having to spend screen time on their childhood while costing just a few lines of dialog.

Maybe the aphorism is "tell, don't show." Dunno. Just woke up. Maybe it's "a picture's worth a thousand words, and vice-versa."