TL;DR: This is a non-issue, and our question rate is fine.
As it stands now, we have:
- around 2k questions (not counting closed or deleted)
- around 5 questions per day
- around 10 answer ratio (answers:questions)
- around 6k visitors per day
- probably no more than 200 active users (high-end estimate from observation)
Think about that, there's five new questions per day with only a couple hundred active users. Considering that each new challenge is supposed to be based on a unique problem, I think that's pretty damn good. Some people can churn out a problem every couple days, but many are here more to answer. That's okay, we need more answers than questions.
The thing is, there are tons of questions if people want to answer. Questions only get an average of 10 answers. Obviously some get more and some less, but they're still there, waiting for more answers. It isn't the lack of good questions that is failing to attract users.
A better question in my mind is: What can we do to get more attention to older challenges? We have tons of older questions that people can jump on, but it doesn't happen that often. Sure, a question or two might get bumped up every couple days by a new answer, but there are tons that nobody seems to look at.
I'm sure the "shiny" factor is the main cause, but it's more of an issue with this type of site then a regular Q/A site. On a Q/A site, questions get answered, full stop. Once a correct, decently written answer comes along, there's little incentive to add to it (unless something changes later).
It doesn't really work that way here (with a few exceptions), because people still vote on new answers to old questions. See an old code-golf with a great answer? You can still golf down a different language (bonus for a different category of language) and get some votes. A code-challenge that hasn't been touched in a while? Give it a shot! You might come up with something better. Many times people will appreciate just seeing a different method of solving a problem, even if it doesn't strictly "win".
As far as "we close a lot of questions" is concerned: Good! Frankly, we get a lot of questions worth closing. What's even better? We also reopen a lot of questions. When I see a question get closed here, it normally boils down one of:
- Clearly off-topic
- Broad/Imperfect spec
There's simply not much to do about the first two categories, every site has them and they just need closing.
Questions with a spec problem are where this community really shines IMO. People generally want to see questions reopened so that they have a chance to answer. We often see long comment threads about what problems the spec has and how to fix it. Sometimes the OPs respond/fix, and it gets reopened. Sometimes somebody else fixes it and it gets reopened. Sometimes it can't be helped and just dies. This works as advertised, and better than on many SE sites from what I've seen.