In this answer responding to a user asking about why their Very Low Quality (VLQ) flag was declined on a blatantly off-topic question here on Meta.SE, Tinkeringbell ♦ mentions,
The VLQ flag IS NOT appropriate for blatantly off-topic questions here on MSE.
And not only on MSE, but it's inappropriate across the entire network.
I've been declining them whenever I see them because people should either flag those posts for closure or cast their close-vote, but NOT flag them as Very Low Quality.
From the Usage guide for very low quality link mentioned on the What is flagging from the decline reason:
You should not use it to describe the following, but should be using close votes, down votes and / or edits instead:
... Questions that are clearly off topic
And:
If you vote to close a question that doesn't show any code and flag it as very low quality, a moderator is very likely to decline your flag as lacking evidence prior to closing the question anyway.
This flag, for questions, has been widely contentious over the years (e.g. see It shouldn’t be possible to flag questions as Very Low Quality, Is the "very low quality" flag necessary?, and Is the Very Low Quality flag too ambiguous?).
Even after all of this time, it still doesn't seem clear what the VLQ flag for questions is really for. Could we have some concrete examples of questions for which, if they appeared on Meta.SE, a VLQ flag would be appropriate (questions that are so bad that a moderator will not, or at least should not, decline VLQ flags), but where red flags (Spam or Rude) would not be appropriate? Appropriately redacted examples of real questions would be great, but if not, it would be very helpful to have some made-up examples of terrible, horrible, no-good, very bad questions that clearly qualify as VLQ but do not rise to the level of spam or abuse.
In response to Glorfindel's answer, I'm really looking to find out whether there is a real-world use case for the VLQ flag on questions here on MSE, or whether it is just a honeypot trap for the ignorant flagger.