"When writing, kill your babies" Basically it means to that you shouldn't be afraid to remove unnecessary parts during editing. Accept that you have to make those decisions. Some characters gotta go, some plot points may have to be complety erased.... but if it's for the benefit of your novel...
If you are still looking for it, I think you may enjoy what I'm writing right now. It's kinda of a battle royale with every human being on the planet participating. It's below on my signature!