This question was closed because it was opinion based. My opinion based flag is declined
This is confusing
I think the flag was declined automatically as a side-effect of the close vote queue. There's a general helpful/declined confusion FAQ (which I found as a result of this exact issue being reported before).
From that FAQ, one way for this to happen is this:
- If your flag was a recommend closure flag, if it receives three "do not close" responses in the Close Votes queue without a single close vote, it will be declined. When you flagged, this is what happened, but later others decided that the question was worthy of closure and therefore closed it.
In case you're unaware, when someone raises a close flag, it doesn't go to the moderators — the question lands in the Close Vote review queue, accessible to 3k+ users. 10k tools show me that the question entered that review queue 8 hours ago, and received three Leave Open responses in a row. If you flagged the question >8 hours ago, this would have meant it was declined.
Later, others came along and the question was closed anyway.
Yeah, that's a bit confusing. Mods are only human though, and they might have had a change of mind after dealing with your flag. Also, there are three of them — it could have been two different mods dealing with the flag and the closure, and mods don't always 100% agree with each other.
There's nothing to worry about though: declined flags aren't some kind of black mark on your account. (There is a tiny bonus from having a flag accepted as "helpful" in that lots add up to a couple of badges, but that's a fairly inconsequential bonus, and a single flag declined won't make much difference in progress toward the 80 and 500 it takes for them.) A close flag is also a fairly small (but useful! keep it up!) thing, so this doesn't represent a significant breakdown of process or anything.
At least, you can rest confident that your judgement was on-target!