The barrier for entry for new users to write challenges is too high. I think there's a problem with how we are closing challenges. There are only two reasons we can close a challenge as "off-topic":
This site is for programming contests and challenges. General programming questions are off-topic here. You may be able to get help on Stack Overflow.
Questions without an objective primary winning criterion are off-topic, as they make it impossible to indisputably decide which entry should win.
However, there are many, many reasons that a challenge can be considered "off-topic" by the community's standards. Your challenge is off-topic by community consensus if:
It's underhanded
It's from another site
It's a popularity contest. In theory, these are not off-topic, but in practice, nearly every new popcon is closed. Nine out of our last twelve popcons are closed.
It's about malicious code
It's about multiple unrelated tasks
None of this is mentioned in our help-center. We should do our best to make sure that any user that goes to the trouble of reading through some or all of our help-center (which most new users won't) has a perfectly-clear expectation of what kind of challenges we want. How is a brand new user that doesn't participate in meta supposed to know that "Do X without Y" challenges are frowned upon?
And beyond being off-topic by community consensus, there are many perfectly valid challenges (Note: not good challenges, but valid challenges) that are closed as "off-topic" because some people dislike them. I don't like that. That's what a downvote is for, but close votes are not super-downvotes!
For example, look at Convert phrases to reverse style [closed]. It was a simple challenge with a very clear spec, that was closed as "Unclear what you're asking". Personally, I see nothing unclear with the challenge whatsoever. It describes inputs and outputs in a simple manner, provides specifications, and includes test cases. That right there is better than most off-topic challenges we get.
Now sure, it's a little bit on the trivial side, but questions cannot be closed for being trivial. (See: Hello world) Dislike trivial challenges? Great I do too! Downvote. You were given downvotes as a means to say "This challenge is not useful", so make your voice heard! Lots of people were also complaining that the challenge is mocking the French Language, and were understandably annoyed. Dislike rude comparisons to a language? Great I do too! Downvote. That's exactly what downvotes were made for. Or even better, edit it out! (Which someone already did) However, as far as I can tell, we don't have a rule stating:
Rude comparisons to a language are off-topic by community consensus.
So until then, nothing in that challenge is worthy of a close vote.
Okay, enough ranting. I don't know what the solution is. I don't think we want to be a clique where the only users who are already active on meta know the rules for how to make a good challenge. We aren't that yet, but I feel like we're moving towards it.
How can we lower the barrier to entry for new users to write on-topic questions? Do we need to update the help center? Do we need more custom close reasons? Is it even feasible to have a close reason for everyone of our close reasons?
However, as far as I can tell, we don't have a rule stating: Rude comparisons to a language are off-topic by community consensus. So until then, nothing in that challenge is worthy of a close vote.
Stack Exchange and all the sites in the SE network enforce something called the Be Nice Policy. In its original form, that question wasn't very nice to francophones. \$\endgroup\$