In Selenium in Python, one of the comment should have been an answer, as (basing on what reported by the OP) the suggestion reported in that comment worked.
In How to create complex data-bindings for webpage <select> boxes?, the OP reported (using other words) that he was asking the wrong question. In such a case, if I would have asked that question, I would have deleted it, or answered to my question and accepted that as answer, if I would have thought somebody could have been interested to the answer.
In python makemessages errors Unknown encoding "utf8", a user asked a question to better understand the situation, but then gave an hint about the error message. Probably that user should have answered the question, pointing out what the OP should have done, instead of adding a comment to give a hint to the OP.
Talking of what you can do in that situations, you can add a comment suggesting that what reported in the comment is really an answer, and as such should be written. I would use comments to ask a clarification on the question, as I did with this question when I asked you to add some links to the questions you were referring to.
I don't think that down voting the questions is correct; they are real questions. If the OP asks a question, and after 5 minutes he reports he found the answer, or that he is asking the wrong question, then I would think that he could have waited 5 minutes more before to ask the question, but that is a different topic.