I got a ms. back from an agent with the brief comment, "Too long, and has too many unnecessary scenes." Okay, it's 100,000 words and you did tell me not to go above 80,000, but I thought the scenes were all necessary. Why didn't she?
Answer: If something doesn't change forever, the scene probably isn't "necessary." For instance:
Two people go for a walk and talk about the weather, then they go home. I don't care how beautifully you describe the countryside, nothing has happened/changed in the story.
Beware, even if something does change, if it's a small something. Two or three "small" scenes, where only something little changes, all in a row, can intensify the "nothing much going on here" feeling. Trust me, Beth. I have done this myself many times, so I do know how it can happen. And I have learned how to fix it.
Here's my advice on scenes.
Every scene should begin with a solid transition that establishes the moment in time and space, tells the reader who is present, and sets the problem/hook statement in the first or second line. Thereafter the action and dialogue develop until the turning point is reached, then a final hook for that scene is set, and the scene ends.
The Scene Ends Right There! Yes, as soon as the point is made, regardless of what else might have really happened later.
Say for instance a medical examiner is called to the scene of a murder. He looks at the corpse and at the uniformed cop on standby, then says, "He's done it again. This is the same as the last one."
That's the final point of the scene, because we have let the reader know a serial killer is on the loose. Now after this scene, the criminalists will descend, take photographs and fingerprints, pick up blood samples, and eventually the body will be removed leaving the inevitable tape outline on the floor, but to show the reader all that would be anticlimactic, because the point had already been established. Once your serial killer is on the loose, end the scene, and get on to the next scene instead of wasting your, and the readers, time on pointless action, however well-written those details might be.
Now, not all scenes turn loose serial killers. Sometimes the point of a scene is as trivial as having an ex-boyfriend call to say he's in town for a week. Okay, that's a turning point. He's in town and he wasn't. A change. But this information might be included in a scene where the turning point is a bigger one. Say your character's next big action is to find a body (sorry, I am primarily a mystery writer). Then you might include the smaller change and write the bigger scene this way:
Your main character, a female PI, is entering a creepy old house, looking for her lost dog. In a mini-flashback, she recalls the phone call from her old boyfriend, Sean, and thinks about their former relationship, while she calls the dog. When she hears scratching noises and her dog whining. She opens a closed door, revealing the body. And the scene ends there.
So the boyfriend change is there, but you don't need to play out the phone call or include their rehashing old times dialog "on stage." Look at the point of each scene and see if you can add the small change to another scene and get rid of the "little" scene, thus cutting the overall length.
You don't need a separate scene for every single change and can combine several changes into one scene, as long as the biggest change remains the focal point.