I have seen many times that somebody voted to close short questions (and probably downvoted the questions as well), even though the OP made clear that there had been good attempts. This thread is the most recent one I saw. While I do not know the real reason that the question has been voted to close, my bet is that somebody looked at the question and thought it was too short to show enough attempt. However, if you really read the question, you would know that the OP must have made it very far in solving the original question. Therefore, I would like to ask you to really read the question before deciding to close it. Sometimes, a short question does show enough effort.
Here is another short question with a close vote that I think is premature. While the OP of this thread should have shown more, to answer the main question why the OP did not get the same result as the textbook (or whichever resources the OP was using) does not require knowing the OP's attempt. By just looking at the information the OP gave, you could see that the OP had actually solved the problem, but did not realize it.
Here is yet another short question with a close vote. The OP properly formatted the question. The OP also supplied a full attempt, despite it being wrong. The only thing the OP should have done more was to add a "proof-verification" or "solution-verification" tag. Yet, there is a vote to close because it is missing context or other details. I am not quite sure what other context should be added to this rather simple question.
This would be my last example for this META question. I only wanted to supply more examples as Xander Henderson had requested. (This is not an attempt to spark another round of heated debate.)