Some thoughts/recommendations on voting-to-close for "Needs details or clarity":
Does the perceived lack of clarity in the question lower Super User's quality as a question-and-answer site in general? If not, then is there harm in leaving the question open in the hopes that someone can answer?
To vote-to-close, we should have enough expertise in the areas being discussion to be absolutely sure that the question can't be answered with the given information. Even then it would be good to second-guess ourselves! And definitely - Ask for whatever information you feel is missing in the comments!
Questions that are not in English are considered (I believe) to be "Needs detail or clarity", but I would hope that the first person to vote-to-close on this basis would leave a polite comment explaining that policy.
I will likely vote-to-close if the question is missing the most basic details. For example, a question that says simply "When I do [xyz], I get *an error" (without specifying the error message or other information) might warrant a VTC. Even in this case, I might consider myself too harsh -- It's entirely possible that another user here could have experienced that and be aware of what the error is, and even have an answer.
But IMHO that lack of detail is too egregious to make it a "helpful" question to others. It doesn't enable search-indexing on the error message, and it's ambiguous (there may be multiple possible errors with different root causes).
I may vote-to-close as "Needs details" if the user including only an image when the output could have been included as text. I may leave a comment in advance of the VTC, or I may just go ahead and do it. It should be noted that users with less than 20 reputation that attach an image are given a warning when doing so that they should include the relevant portions as text, so they have (intentionally or otherwise) ignored that warning already. I'm not sure another "warning" in the comments is justified, but I sometimes give it nonetheless.