A cracking post on the always-reliable and delightfully crabbit Nicola Morgan's blog nails some of the reasons why so many aspiring writers overwrite. Not that I worry much when students' work is rather over-written, because it does usually come from a very honourable state of being drunk on words. As Peter Wimsey says in Gaudy Night, he finds it so easy to get drunk on words 'that to tell the truth I am seldom perfectly sober'. But as anyone knows who's ever tried to revise a piece of work when they're two glasses down, sobriety is also necessary to the writing process, and Nicola's post is very good at explaining how to spot over-writing and what to do about it. It's nowhere near as simple as too many adjectives or lots of fancy words, nor a matter of too much description and not enough action: it's a matter of knowing what you're trying to say and what's clouding the message, and also knowing the context, because what's over-written for one character or voice might be perfect for another.
Because over-writing is perhaps the natural tendency of the majority of aspiring writers, and because having a ruthless eye for superfluous words is the only way for any writer to keep their writing profluent - flowing forwards - much writing advice is to cut-cut-cut, murder darlings, take out one word in ten (literally, decimate), and so on. It's true: it almost always makes it better. Many - perhaps most - writers therefore, as an integral part of their process, reckon to over-write, since only once they have worked the story out into prose will they know what needs to stay and what must go.
But in my experience a minority of writers, but a significant minority, aren't cutters, but adders. And it's my experience because I am one. It's not that my agent or editor has never told me that something isn't earning its keep, is said twice, is over-stated or goes on too long. Particularly if I'm unconfident about a scene, either for internal reasons (perhaps the situation and voice makes it at risk of cliché), or for external reasons (a sniffy blog review has made me self-conscious), my lack of confidence makes me lose my writerly compass. Sometimes it's just that the documentary desire to evoke a place I've actually witnessed or researched makes me do the same.
But my editor's comments are more often that I haven't written something out fully enough: that we need a little more about why she said X, or why he felt Y, or what the ship smelled like, or what they saw that frightened them. If I'm driving a scene towards a climax (and why would the scene be there if I wasn't?) then in the typing up I may realise that I haven't put anything except dialogue and the essential relationship of the bodies: the leap to the feet, the gaze, the touch of a hand. And yet the scene is very likely to need something which you could say is surplus to requirements in crude storytelling terms: things which in other forms would be supplied by the scenery, the cameraman, the light on a cheekbone or the atmosphere of the score. It might be a remembered phrase from years before, a metaphor which holds all the terrors in a word or three, a single burst of eloquence from a normally taciturn character in extremis. It doesn't take much, and the advantage of adding, if it's your natural tendency, is that you've got the balance and rhythm of the sentences and scene already formed: it's easier to see what's the right amount and what's too much. But the scent of a snuffed candle, the cold wood of the floor under your feet, the street lights sprawling across the ceiling... these things make the world of your novel live and breathe.