To me, many of the available close reasons are a way of saying to the author "This question has serious issues and you need to take some remedial actions to fix them". It makes sense to me that we should be visually prompting them to take those actions via a notification rather than just hoping that they care enough to keep checking in on the question.
When would this be useful?
If you can think of any other situations where this might be useful, please suggest them in the comments.
I can think of the following scenarios where I would find a close notification potentially useful:
- When I've posted a question into a low traffic tag
If I use one of my own questions as an example. That question is around a month old, it has one vote and a deleted answer. Over the course of its life, that question has attracted just 47 views, with most of those probably being in the first few minutes after posting. Do I check that question every day? Good lord no! Frankly it would be a waste of time for me to do that (admittedly not a significant one). If it was closed right now, I probably wouldn't notice it for a couple of days because I don't consider it to be active, so don't check on it anymore. This is somewhat related to...
- When the question is no longer active
Most of the activity on the vast majority of questions happens within the first few hours after posting and then nosedives to almost nothing[Citation needed]. We can't reasonably expect everyone to keep close tabs on their inactive questions to see if anything happens to them.
- When the question is closed as a duplicate
To quote TheLQ:
This would be especially helpful for duplicates, where the answers you need are already there. A message to the effect of, "Closed as duplicate of question" is just like notifying me that a new answer has been added!
There is also some situational value to having a notification. I completely understand Jeff's view:
You should care about your question more than any other human being on the planet. If it is closed, you should already know about that without needing a special magic notification.
And in an ideal world this would indeed be the case. But we don't live in an ideal world, and not everyone sticks around after posting. Some people will wander off completely thinking "I'll check back later", we can't really do much about that and a notification won't be of much use there. But other users will stick around on the SE network. Perhaps they'll go and read a few posts here, or on a child meta, or just hunt for questions to answer on their main site. Those people would benefit from being notified of their question being closed.
Opinions are like...
...so here's mine: I feel that the benefits of being notified about question closure outweigh the negatives - I'd rather have a notification telling me something I already knew than not having one telling me when I hadn't noticed. Per user, having a question closed should be a rare enough occasion that it's not going to cause a huge spam of notifications, and if you consistently ask good questions you should never notice this anyway. I support this.