When reviewing low quality question, a common reason for me to recomment closing is that it is not clear that OP made any effort in researching or answering the question himself. I then often take the "unclear what you're asking" flag, because in a sense I do not know where the problem is when they do not tell me what they tried.
What is the correct flag for lazy OPs? Is this even a reason to flag? If so, could the flag options be made more clear so that I know what to choose?
Is there some way to see in beforehand what this flag will look like to the OP? It would be nice to see the exact message. I often saw a (probably machine generated) comment below such question that say something like "please show us your approaches", but I have no idea which action of mine will result in such a comment.