When it comes to writing a text what I am trying to do is to move everything forward at the same time. That is plot, setting and character have to evolve together, not one after the other. This is especially important at the beginning of a book where you are trying to draw a reader into your world. The writer must give them as little excuse (or time) to slip away as possible. If a reader feels they are putting in too much time on stormy weather, baroque architecture or rocky escarpments their mind can wander. If you go into dense characterization or, worse, heavy back story, you will hear the thunder of readers hooves moving off to new pastures. I reckon you have a maximum of ten pages in which to position your central character in his/her life with friends, family and relationships, in an atmospheric setting with a plot up and running. You can (partially) fail on the first two counts but you must not fail with plot.
read all his thoughts here
(Hat-tip: The Rap Sheet)