Questions that are closed as off topic or not a real question automatically carry a downvote. These are what I call "fault" closes.
Questions that are closed as "duplicate" or "too localized" do NOT carry a downvote. They need to be closed for the sake of the site, but the questioner is not expected to know that, and the close is "no fault."
Right now, "not constructive" is considered a "no fault" close. But I can think of TWO versions of "not constructive," one of which would be a "fault" close, and one of which would be "no fault."
This would be the "fault" version, which I would describe as "subjective and argumentive":
As written, this question will likely solicit debate, arguments, polling, or extended discussion, although it might be answerable in a different form.
This would be the "no fault" version, which I would describe as "not constructive":
This question is not a good fit for the site. It will likely solicit debate, arguments, polling, or extended discussion because there is no known body of fact or literature on which to reasonably base an answer.
The downvote for the "fault" version would reflect a belief that the question could be improved, and encourage the OP (or other editors) to do so.
With a "no fault" close, the question can't be improved BY DEFINITION. But it also reflects the fact that the OP did his "best," and that it is being closed because (like duplicates and localized questions) it is BAD FOR THE SITE as opposed to being "objectively" bad.
Should we separate "not constructive" closes into "fault" (subjectie and arugmentive") and "no fault" ("not constructive")versions as outlined above?