Five adjectives are better than six. Four adjectives are better than five. Three are better than four. Two are better than three. By using fewer words to obtain the effect you desire, you will force yourself to use more accurate and powerful words.
Communication is the primary job of the novelist.
The kind of prose that most powerfully communicates ideas is simple and direct. You can't entertain a reader if he doesn't understand the story-line. You can't affect your reader emotionally if your prose is so dense it weighs him down. Good prose contains vivid metaphors, similes, and striking images. A novel would be flat and dull without them.