So she's setting people straight, with some advice about submitting and writing that anyone who is submitting a manuscript or writing anything that they intend to publish would do well to study, memorize, apply, and copy onto their bathroom walls so that they must consider the wisdom of Miss Snark. Not being agent, I care especially about the following two:
2. Sitting in a car/truck/bus, telling me about the weather you're having is not not not compelling. Not now, not ever. Go rent a copy of the movie Jaws. Watch the beach scenes without sound. Not quite as scary is it? Here's the thing about novels. You have to show me the sound effects. Your writing, your diction, your pacing, your POV, your choice of focus, all have to get my attention and point me at the shark. You don't have to show me the shark, but I have to get a sense it's there.
In general, avoid descriptions of the weather, the scenery, or anything else that doesn't make me wonder "What's going on? What next? Who are these people?" and also make me want to know the answers to these questions.
7. Look at every use of the word "was" and "that". 90% of the time you can take them out. That edit alone will jump you over about half the stuff I look at every day. Prune ruthlessly.
In other words: Rule 17*: Omit Needless Words. Scrutinize every modifier: Does it need to be there? Examine every verb: Could it be more lively, more precise? Is it in the active voice? Could it be? Never use three words when you could use one.** Make every word, every phrase work.
Writing is work. It's hard. It's more than putting words down, as they crawl out from under your fingers. It's a craft, and it can be learned, and if you want to write, you need to apply yourself to learning how to do it well. Nobody wants to read mediocre, overstuffed prose. Trust me: I do it all day, some days, but someone pays me to make sure other people don't have to suffer.
And Miss Snark knows from writing, so heed her words.
* Also known as the battle cry of the line editor.
** Of course, you should omit only the needless words. Keep the other ones, but make sure they're the ones you need.