If you take a few days to write an outline, you're just making up scenes that you think will work, that you think will be interesting. But as you write it, other ideas occur - better ideas that have to do with what you're writing.
Elmore LeonardDon't go into great detail describing places and things, unless you're ยญMargaret Atwood and can paint scenes with language. You don't want descriptions that bring the action, the flow of the story, to a standstill.
Elmore Leonard