So your bones are there, begging to be fleshed out and dressed.You work through your scenes and find one you just love. It has all the right elements, just enough description and dialogue. You're so proud of it you could just burst but...
You read it and realize that this perfect scene doesn't help move your plot. What to do?
Your desire is to leave it there, after all you worked hard on it and it deserves to be read but no matter how wonderful that scene is you have to be strong. Take a deep breath and decide if you can edit it so it does help your plot or cut it. I know that hurts. No one wants to destroy something they worked so hard at but you need to be clinical when you look at a scene. If you don't, someone else will, and that can hurt a whole lot more.
Every word should move you to the goal. Character development, subplots, they still need to take your reader to the climax of your book.