Recently, the question How often should one evaluate a plan for an academic career? has been closed without a single comment explaining why it should be closed, while there was already an upvoted answer.
I decided to reopen the question, because the next logical step is to delete the question, and I have no idea why it should be the case, and it's likely we're stuck with an "on hold/closed" question. As I already stated here, comments are very helpful to maintain the site, especially that we are still on beta, and that we don't exactly have hundreds of questions each day. Helping a new user understanding why his/her question is too broad or off-topic is important to help the community grow.
To be clear: I'm not saying that this question should necessarily be kept open or should be closed, but if you know why you're closing the question, then leaving a comment should not be that difficult, and if you don't know why you're closing the question, then perhaps you should not be voting to close in the first place.