Is there any serious disadvantage to publishing blog posts and improving them later?

I am considering posting a lot of different articles on my blog, but I’m kind of a perfectionist. I’m trying to overcome my “blogger’s block” by telling myself “just publish whatever (decent enough, of course) and improve later eventually”. But now I thought — will this affect SEO rankings or anything? If I update posts later on? Any other disadvantages you can think of? Thanks!