Well... the post is editable for a few days. And then it's locked. And the content is available for eternity. So, me... I always edit my posts. I sometimes just don't see my errors until the next day. And sometimes I'm just too tired if I'm writing a post late at night! So, I'm all for touching things up later, since I know it may be something someone comes across next week, or next year, or five years from now! :-)