This is mostly about formatting.
Whenever I see a post that does not uses the proper formatting somewhere on it I edit the post and add it. The problem is, sometimes it's a really small thing - or sometimes the question is still perfectly understandable, it just looks terrible.
I am mostly concerned that I'm wasting my time and the time of those who actually have to review my edits. Some people may consider some of my changings too superfluous to matter. In my defense, well, maybe I'm just a bit of a perfectionist when it comes to those things and I do believe they matter.