flags should not be used to indicate technical inaccuracies, or an altogether wrong answer
Well this basically answers your question but I guess you're trying to get at the motivation behind it. There's no one-size-fits-all answer to that from what I've found, though this meta post covers the basics.
Generally put, as moderators we should not judge answers for "correctness". We are a small team of exception handlers that deal with things the community can't handle. The community can and indeed should handle bad answers. Downvotes and comments are the tools at your disposal for that. Flags are not, at least generally speaking.
One thing to add here is that this practice originated with the more technical sites. A moderator mainly active in Java and front end design wouldn't be able to handle questions around compilers or low-level programming. It makes no sense to let them judge how correct an answer is. This is somewhat different on The Workplace of course. Though even here it's hard to judge matters related to specific country/state law for instance. That's also an area where the moderator handling your flag might not be well versed in. If the OP says the law is X while the flagger says the law is Y instead, it's not up to the moderator to make a final call. Instead the flagger should leave a comment and downvote and allow the community to take it from there, presumably leading to more downvotes and potentially deletion votes.
When flags like this reach us it's always a judgement call. There are instances where we delete these. Typically when criminal behaviour is involved in an answer or anything similarly "over the line". Advice that would get someone fired will sometimes rise to that level as well, but most moderators will prefer to leave those calls to the community. In cases where the post is already downvoted or it's otherwise clear that it won't do more harm we tend to decline the flag because the community has already handled the post.
There is actually a very good example of such an answer on that same post. This deleted answer advocated violence in the workplace. It would have been nuked on sight if a moderator had spotted it before the community deleted it. But even there the community was faster than us in getting the post removed. :)
Hope that answers your question, but let me know if I should elaborate on anything.
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