As someone who makes a lot of edits, I'll share the general rules that guide my edits.
I see editing questions as a really important part in site improvement.
Almost all my edits are on questions. There are many reasons for this:
- Votes sort out whether an answer goes to the top, but a question will always be at the top.
- Many questions are asked by users new to the site who don't know all the theory of Stack Overflow of asking good questions. They also often aren't concerned about the broader goals of creating an Inteernet artefact that is readily consumable in the future.
I make many edits to questions, some of these include:
- Ensure that the title captures the essence of the question in a concise and accurate way. Question titles are really important for search and for interconnectivity on the site; the title should make clear what the question is about.
- Make sure that it is easy to identify the actual question. E.g., put question text in bold; for questions with a massive build up, add headers flagging background content and the actual question.
- Fix spelling mistakes, grammatical errors,
- remove words like "many thanks" or the person's name
- Remove superfluous introductions.
- Rephrase a statement as a question
I'm always mindful of maintaining the original intent of the person asking the question.
If I'm at all concerned, I'll often make a note in my edit along the lines of "feel free to edit if I have misconstrued".
If I'm worried that an edit has changed the meaning or scope of the question, and there are existing answers, I'll add a comment.
- Occasionally I'll add a few references, fix up a typo, or if I've found the PDFs for some references, I'll add these.
- Some answers are framed either explicitly or implicitly as open to editing; e.g., an answer is designated to be an approximate policy on meta (at least that's how I interpreted this one about references) then it makes sense to edit that; or occasionally the person asking the question, invites additional input
But ultimately, I'm happy for the voting mechanism to sort out what makes a good answer.
Update - some thoughts on whether to make minor edits
Both Stephen and Josh have raised the topic of ensuring edits are substantive rather than minor.
The two major concerns with minor edits seem to be (1) inappropriate bumping and, (2) the risk of inappropriate conversion to community wiki as a result of too many edits, which presumably means that rep no longer accrues. (The community wiki status can be removed by moderators).
I agree that fixing everything in one big substantive edit is a noble goal when time permits. However, when time does not permit, one needs to decide between making no edits or just making the edits one has time for. The line between trivial and substantive is also open to interpretation.
With regards to editing causing a question bump, this is only relevant to questions that are not already at the top of the queue. Thus, editing has minimal effect on the exposure of new questions as they are already at the top of the queue. In my experience, a lot of the edits I make are to questions shortly after they have been posted.
I see the issue with community wiki conversion as a little more problematic. However, (as I understand it) it does take five separate people to edit a question. I don't think this happens too frequently. Also, if someone is unhappy that a question has been inappropriately converted to community wiki, they should feel free to flag the question to moderators to conversion back to non-community-wiki.
Thus, the above two points argue that the negative consequences of edits are actually pretty minor.
The main point about edits that I would make is that editing questions is a behaviour that is not especially rewarded by the site, but which can dramatically improve the quality of the Internet artefacts that the site generates. A good title allows people clicking links on the site, or following google searches to know whether the link is relevant before even reading the article. A good retag improves the interconnected nature of the site's questions. Clarifying the question helps readers see at a glance what the question is actually asking.
If anything I would encourage skilled users of the site that are familiar with the conventions of good question writing to tactfully edit and improve questions, particularly as they are posted.