It is my understanding that casting a very low quality or not an answer flag on an answer that already has received such flag only affects the flag statistics and the number of positive reviews needed to dequeue. Thus, if:
- I have access to the low-quality queue (2 k on graduated sites),
- I see an answer that I deem deleteworthy,
- I suspect that somebody has flagged this answer before me (which is almost always true and can be certain if I see a canned comment),
it is more effective to go to the low-quality queue, seek out the answer and choose Recommend Deletion/Delete, while flagging it has most likely no effect. This is tedious for those who act accordingly and a waste of decisions from those who just flag.
Moreover, it is not that obvious for many that after becoming trusted users (20 k), they can do something else with deleteworthy and negatively scored answers, namely directly voting to delete them – which is mostly equivalent to what they can do from the low-quality queue. Again, decision capabilities are not used optimally.
I thus suggest the following for answers that are already enqueued in the low-quality queue:
A VLQ or NAA flag from a user with a reputation between 2 k and 20 k should have the same effect as if this user had chosen Recommend Deletion in the low-quality queue.
A VLQ or NAA flag from a user with a reputation above 20 k should have the same effect as if this user had chosen Delete in the low-quality queue and automatically cast a delete vote if the answer has a negative score. (And while we are at it, a delete vote should automatically cast an NAA or VLQ flag.)
Some considerations or non-considerations:
I haven’t made up my mind how exactly such flags count towards review and flag statistics.
Probably, something needs to be done with users who have performed the maximum of daily reviews in the low-quality queue or are review-banned.
This deprives 2 k users of the ability to plainly send a post to the low-quality queue, which may be a good choice on rare occasions where you are unsure about a post due to lacking topic knowledge. On the other hand, if that post is already enqueued, you are likely making the right decision and if not, at least two other people need to make the same bad decision.
Also note that the suggested feature would work similar to closure flags in this respect, which are automatically converted to close votes for 3 k users.
An easy way to implement this would probably be to rescale delete votes and have them work like close votes: Allow 2 k users to cast delete votes on answers, double the weight of delete votes from 20 k users on answers and require six or seven delete votes to remove an answer. Auto-cast delete votes on VLQ/NAA flags from such users and automatically enqueue posts with such votes.