There are already many Q&A related to the improvement of a question by the original author. It is quite obvious and well documented how to proceed to improve the form of a question. However, I did not find guidelines or discussions about the case of poorly formulated questions that will probably be proposed for deletion but someone else could transform into good questions by adding a knowledge the OP is probably missing.
The Help Center says
Edits are expected to be substantial and to leave the post better than you found it. Common reasons for edits include:
... To clarify the meaning of the post (without changing that meaning) ...
My question is about the reasonable limits of clarifying the meaning of the post. For example (but, please, take it just as an example, it is not the focus of my question), today I saw in the Close vote list this question.
I think that the OP should have used the comments to improve the question. However, he/she is new to the subject matter of the question, ii) and a newcomer to this site. As a consequence, no modification was done, and the question is going to be closed. What is the general feeling about the best behavior? Leaving the question in its original state or adding enough details to transform it into an acceptable question?