As a writer, you have a huge responsibility to your fans to ensure that they are engaged by your writing on every page of your book. There can be no unnecessary pages.
This means you will have to review each page carefully to see if you have provided something that will capture your reader. This also means that you will have to be honest with yourself and be willing to change passages in your book that simply move the plot along.
Get in the habit of checking each page and your readers will love you for it. Go the extra mile and you will always have many miles of writing ahead of you. Cheat your readers and your writing career will be over before it ever really got started.