The purpose of every scene is to advance the story. A second and equally important purpose is to reveal something about a character. This revelation can be something new or something different that reveals the same characteristic.
For example, in “Ghostbusters,” an early scene shows Bill Murray electrocuting a young man to make him go away so he can be alone with a pretty co-ed. That shows Bill Murray’s character as someone who’s always chasing women.
A later scene shows Bill Murray’s character as he goes into Sigourney Weaver’s apartment to investigate supernatural events. While pretending to look for a ghost, he’s really trying to get the attention of Sigourney Weaver. This is the same information but repeated and told in a different way.
On the other hand, an early scene in “Butch Cassidy and the Sundance Kid” shows how good he is with a gun. Then a later scene when they’re trapped on a cliff reveals that he can’t swim. That’s new information.
When revealing information about a character, a scene can repeat and reinforce previous information, or it can show us something new. What a scene cannot do is not show us something new or reinforce previous information.
Just by keeping this in mind, your scenes won’t feel flat and dull just as long as you find a way to dramatize the information to reveal. In “Butch Cassidy and the Sundance Kid,” the Sundance Kid’s revelation that he can’t swim is funny because Butch and the Sundance Kid are trapped on the cliff and have no other option to save themselves other than to jump into the river below.
If the Sundance Kid simply told Butch that he can’t swim before they were trapped on the cliff, this information wouldn’t be as funny or memorable.
So make sure each scene reveals new information about a character or repeats (reinforces) previous information about a character in a different way. That will keep all of your scenes feeling important and necessary.