This question seems to suggest that it's common knowledge that it's not to be encouraged. However, if there is a simple (and usually really short) answer, should I not vote to close it and answer instead?
What is meta?
- Any Stack Exchange user can ask a question
- The community provides support, votes on ideas, and reports bugs
- Your voice helps shape the way Stack Exchange operates
Situations where this can be okay include
when doing this, always consider whether it's worth making your answer Community Wiki - seeing as the question's closing will deprive your fellow community members from adding their competing answers.
You answer because you want to help the person asking the question, you close because the question is not a good fit to the site. The two are separate decisions based on separate value sets: it's perfectly reasonable to do both.
But be aware that the points you might get for answering the question are in jeopardy, because the question might be closed and deleted based on your other action! I for one have done this at least once, answer a question and vote to close and add a comment explaining why I'm voting to close.
When voting to close (really migrate) as off-topic, belongs on another site, I think it's perfectly acceptable to also answer if you can. The answer will be appropriate even if moved. Under other circumstances I would probably comment, if anything, to help the user out. I'd rather not encourage users to ask bad questions, or repeat ones for that matter, by providing an answer. If the OP seems genuine in asking their question, they're more likely to get a helpful comment, but that's just me.