In Kathryn Stockett's beautiful novel THE HELP, she reveals character by showing the contradictions between a character's spoken words and her actions, letting the reader understand the character in depth via what she leaves unsaid. For example, Minnie mouths off to her dimwit, yet sweet employer, speaking disdainfully about Miss Celia, as if she cares only for the job and not at all for the pitiable boss. She denies Miss Celia's assertion that they are friends. But when Miss Celia falls ill and collapses onto Minnie's shoulder, Minnie states off-handedly that tears spring into her eyes, even as she quips that she is not sure what the maids' rules are regarding responsibilities for white ladies dying on top of them. The reader can see through Minnie's false bravado without Kathryn Stockett having to tell us that Minnie has a soft spot in her heart for Miss Celia. That kind of writing, the kind that shows rather than tells, shows respect for the reader's analytical abilities. That is what I consider ENGAGING writing, the kind that readers remember because they had to interact, in a way, with the characters, rather than merely absorb the author's interpretation of the characters.
If Kathryn Stockett had written, "But Minnie was hiding her sympathy for Miss Celia, of course," I would have rolled my eyes and thought, "Gee thanks, I would never have figured that out on my own...duh!" But this author did not overwrite as beginners often do, and for that I thank her and offer her as an example for aspiring novelists to study. I must point out that her choice to use multiple first-person narrators, instead of an omniscient third-person narrator who gives readers their glimpses into the characters' points-of-view, definitely prevented intrusive overwriting. Stockett thus set up boundaries for how much she could tell readers through a character's own mouth and still sound natural. After all, Minnie would be the last person to confess her vulnerability to others; she doesn't even show weakness to her best friend in the story.
Writing is as much what happens ON the page as what happens OFF the page--in the reader's mind.