It is not enough to edit your words.
You must also consider your meaning - your intent - your what's it all about mate. If your characters and the events that happen to them have no meaning there will be no impact. That hard fought for reader will walk away and never come back.
Here's a handy little exercise - write what your book is about in one paragraph. Yes just one. Then write what it's really about in one sentence. If you can't do that then your book isn't ready. You're the writer and if you don't know what your story means then there is little hope your reader will.
Ask yourself - do your characters feel natural or appear alive? If not then find out why - is it in the way they move or speak or interact with other characters. Which lines don't work? Dialogue must fit the character, it needs to be consistent but in-line with their development, keep it succinct and be exact. Dialogue speeds up a novel and creates pace but remember, lack of dialogue can also be very strong. Are your character names appropriate and distinct? Look out for similar sounding names, they can get confusing. The reader doesn't necessarily have the same familiarity you have with your characters, don't forget you need to describe all that intricate detail fizzing around in your head. If a character is a walkon - leave them as a walkon. Give them too much attention and the reader will be wondering where they are later in the book, this is a distraction. Distractions are bad.
Another piece of advice is to record your novel. Read it aloud, chapter by chapter, page by page and save the recordings. Once you've finished, listen to them. It's quite possible you'll hear problems when you're reading the words aloud but you will definitely hear them when you listen to the prose. We are looking for a balance between dialogue, description and action but they are your words so you will know when it sounds wrong.
Write the beginning. Write the middle. Write the end. Get rid of the beginning and the end. A good quote but maybe we don't need to be quite as brutal as that. It's worth bearing in mind that the start of your book represents you finding your style & story and the end of the book represents your reluctance to let go.
And so we come to endings. They need to have an internal logic that matches the meaning of your story. They have to make sense. It does not matter whether they are satisfying or whether they tie up all loose ends, that depends on the type of book you are writing. Your ending must be the only ending possible. Concise.
