When writing, and designing adventures, and game supplements, there is a temptation to bash in with powerful, evocative scenes, and long-winded descriptions. There's a writer in each designer, and a designer in each writer, and it's important to be able to draw the line between the two, and to adjust to it in order to produce interesting, gameable things.
Too long a description, and you strip the DM of his storytelling role. Too scripted a scene, which you need to do if you want it to reach narrative impact, and you railroad the players, and eventually confine their game to your imagination, and space instead of letting it unfold at each game table as it should. As always, scarcity is the sign of success. Sometimes, it's half of a hint of what might happen hidden in a stat block, or an otherwise innocuous location key. An adventure is a minefield of hooks, and triggers. You can play some of these triggers mechanically by embedding them into the system — giving a gust of wind spell to enemies, for instance, so that torches will be snuffed, or setting high chances for wandering monsters, and preparing an especially gruesome monsters' list can both lead to horror situations. You don't need to say how horrible this all is, just to setup things so that the horror will happen during play, by itself. Or you can plant the triggers with flavor, giving a distinct tone to the adventure.
Whatever the method, you're bound to miss the mark if you overdo it, and start to TELL. It may not be as attractive as a good book. There's a reason for that: it's an adventure, which is meant to happen during play, and not a piece of your imagination that you're suppose to impart, and port to game tables that will be forced to configure themselves in order to play your thing. Follow this track, and you end up with a coffee table book, a novel, an interesting thing possibly, but not with something people will play, and have their fun with.
That's why the best adventures may seem bland to the beginner's eye sometimes, think Tomb of Horrors. Where's the demilich background? Where are the powerfully evocative room descriptions? What's the reason for the traps, and how come they're not fully described as the horrible over-the-top thing they obviously are? Because you find this all out, DM, and players included during play. That's why we remember Tomb of Horrors, and will forget coffee table books. In Game Design, everything is attention to details, not to the powerful, the scripted, and the poetic, that you should keep to the writer's side. We can be both! But there's nothing worse than a frustrated writer designing games, or a frustrated designer writing books.
As readers, and DMs, we need to give the same attention to details. Small, puny figures, and numbers, and maybe an adjective here and there: that's where the fun that's going to come is hidden. Game Design isn't an Art, it's a Craft. That's, personally, how I craft adventures, and random generators — not saying I'm successful or not, up to you to judge from what you play— I plant seeds, little mechanical systems that I know will trigger scenes all by themselves, a word here, a precision there, so that piece after piece, building block after building block, I know that it will shape a memorable adventure that will make sense as a whole, during play.