I've had a couple of circumstances where this moral dilemma has arisen: The asker's question is really off-topic by all counts and is already receiving downvotes. I can downvote now, but I also want to be helpful.
Is it ok to downvote the question as off-topic and unsalvageable and still answer or at least comment to the user to try to assist them? Or is that considered encouraging off-topic questions?
To clarify, I'm not talking about commenting to help them ask better questions, I'm talking about trying to answer or guide them toward an answer while downvoting their question.