Suppose an OP poses a question without showing any effort, any research. Obviously, we should not write an answer as such. I think all the regulars on this site are on the same page about that.
But I want to focus on the effect it has on the OP to give him the information he's requesting via a quick comment, without providing feedback and without waiting for him to revise his question.
Should we avoid this? I think yes, and if you agree, please upvote; if you disagree, please downvote; if you think things are more complicated please feel free to write your own answer to this question.
Reason for my "yes" to the question: providing the requested information in a quick comment is unlikely to train the new participant to follow the guidelines for writing a good question. In fact, this approach might teach the new participant that he can just toss off a quick, unresearched question, and get the information he is seeking here, without any effort.
I do want to acknowledge that the quick comment was clearly coming from the best intentions imaginable.