One thing I think writers tend to do is tell motivation. I think sometimes we want to explain a character's past and why they're doing something.
I'm not talking about backstory dumps or huge paragraphs of telling. It could be only a line.
The movie Georgia Rule inspired this post. The granddaughter tells someone she was molested, but then she says she made it up. The viewer is left to figure out the truth based on nothing more than the character's actions.
That's showing motivation. In the movie, we're not told:
The mom's an alcoholic so the daughter is an enabler Instead, the daughter acts in certain ways and the informed viewer can guess at her motivation.
The daughter was molested Instead, we're shown how the daughter acts with the opposite sex and we're left to draw our own conclusions on why she does what she does.
It's tempting to tell the reader why a character is acting a certain way, but sometimes I think the story is much stronger if we let the reader intuit the reason.
Do you like to tell motivation rather than use actions to show it? Did you see this movie?