If you go the extra mile, you’ll end up a mile past where you want to be. – Peggey the Editor.
Truer words, as a writer, have never been spoken. Of course, the picture below lies. Lies big. Lies like the dog in front of the door who doesn’t want to move and insists that you rub his belly before making your way out of your house. Yeah, it’s that big of a lie. Let’s expose it for what it truly is to everyone out there: one big, fat, stinking, baldfaced LIE.
So how do you know when enough is enough? How do you know when the time is right to lean back, look at your monitor (or piled sheets of paper next to your ancient typewriter… dear God man, buy a computer!) and say “I think… this is done.” Usually that last saying is followed by a “?”, a moment or five of disbelief, then jubilation. Wonderful, blissful jubilation because this cursed book is finally done. But then…
Then you look at it a little more. It could use some more infodumps, maybe an extra explanation… no. Stop right there. Really. 120,000 words for a first novel is really good. Plus, that makes it about 500 pages roughly. Put it aside. Let someone else read it. See what your wonderful first readers (people you know who give up their valuable time to dissect your book for free) think of your work.
Then, and only then, do you go back and see not only what you should add, but what you may have to take out. Because if anything, things can be removed, cut and shortened in a book easier and quicker than lengthening the thing.