There were two close votes on question 41667 when I added mine, but there was no explanation given in the comments as to why the close votes were cast. Since a user has to have 250 reputation to see close votes, might this mean that if we close votes without comments, that we're closing questions where the user asking the question does not see the reason that close votes are being cast? If so, is this the way we want it?
I think some actions should be commented. Close voting is one of them. It's not required, but it's just polite. It's also better for the site and will help retain quality contributors.
SE is a confusing platform. It's unique and there's a lot going on. I think many of us who have been around a while take for granted how easily we now stroll along through the site.
Having your question "closed" is a foreign concept to most people. "You mean you won't even let people answer my question? It's not that bad!" They deserve a reason better than the cookie cutter responses in the close dialog. More than that, they need a name to ask for help, because the existence of meta is not apparent either.
Lot's of new users are drive-by's. They will just swing by when googling for something else, decide they have a question of their own, ask it, then never come back to even check on it. Others read for a while and get it before they even ask a question. Then there's others in between that we could sink as regulars if the right things come together at the right time for them. That takes direction. People like to be helped when they're confused, and let's face the facts, SE is quite confusing to a newbie.
I just took a look at the front page of Physics.SE, where I currently have 235 reputation, and I can see that this question was closed as "unclear what you're asking". The 250-rep limitation applies only to seeing the close votes (e.g. 1 "duplicate", 1 "off-topic", 2 "primarily opinion based") and not the close reason after the question has been closed.
I am sometimes guilty of closing without a comment, but sometimes the close reason says what I want to say, so I feel like there's little reason to repeat it.
EDIT: upon clarification, I see the question is really more about the courtesy of commenting on a new user's question to explain why their question is being closed and/or help them fix it up. In that case, I agree that this is a good thing. It is good and courteous to help a new user understand how this site works and why certain actions are being taken.
That said, I'm lazy. I know that there's a tool that fredsbend, David Stratton, and Caleb (I think) at least use to type in pre-written comments. I don't use that tool, so I comment less often and with less to say. Quite often, the question is pretty poor and I feel like if the user put that little effort into the question, I'm not going to waste my time writing out a good explanation/educational comment. That's how I do things, but otherwise, I support the idea of commenting more often.