How refined do posts need to be to not suck? (50) - Incrium

People like Paul Graham say that they spend a lot of time editing/writing their posts. Is this necessary for posts to be good?

What makes a post good?

The measure of the value of a post should be the effect on a reader. A lot of topics require well written, well argued essays to be good; I think though that you can write plenty of useful things on which not much effort was expended.