Last year I asked this question on meta about whether it's ok to answer off-topic questions. Today I saw this question from a new user which is clearly off-topic, but somebody had taken the trouble to answer it anyway, and seeing no problems with the answer, I upvoted it.
Now, maybe my Japanese is even worse than I thought and the answer was in fact wrong, but I was surprised to find that the answer had subsequently been deleted by a moderator. It doesn't seem to me that this is a good way to encourage people to answer questions, and leads me to once again ask about our policies on answering off-topic questions.