In this stack example somebody has down voted the question without a comment. How will the person asking the question know what he has to do or what other details he needs to provide?
@RedDevil You're right, it'd be hard/impossible for someone to know what to do to make their question more well-received without any input. In similar situations in the past, I've added a comment myself that make a best guess at why the question hasn't been received well (in this case: lack of detail, no indication of previous attempts or research, sounds like a 'write it for me' request rather than a 'help me overcome this problem' request) and perhaps point to the help/how to ask pages.
Also, I'd encourage you to not fall victim to the bystander effect. Instead of waiting for someone else to help out, be the one that does help out.