This question has an increasing number of vote close. However:
- it has no bad number of votes.
- answers has good number of votes.
- reading answers and comments, it is show that is not off-topic nor an obvious question nor duplicate.
Yes, can be is not totally clear (could be that if someone is able to write a totally clear question, he/she doesn't needs an answer).
The description of "unclear what you're asking" is:
Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question.
So, the discussion is: should a comment be mandatory for close vote - unclear ?
In my opinion, if a question is unclear, comments are received and author doesn't improves it, it must be closed. But questions that the author is taking care of them should not be closed. It is difficult to clarify something if the doubts or unclear points are not expressed.
Worst, my experience says that questions that are about subjects not usual or repetitive tends to attract this kind of close votes. If we block this kind of questions, the quality of the full site will fail.