In general, when I see a greyed out comments, I can understand why they were downvoted. But I occasionally see downvoted comments that seem totally legitimate.

In general, when I see a greyed out comments, I can understand why they were downvoted. But I occasionally see downvoted comments that seem totally legitimate. If someone feels negatively about a comment (for reasons other than it being nonsense or off-topic), the mature thing to do is to explain their disagreement with the comment. I agree that asking "why the downvote" is rarely productive. But downvoters should explain their point of view in addition to (or instead of) downvoting.