I'll preface this by saying you can't force people to accept answers.
It sucks, but that's the way the system works: Some users will simply never accept an answer on a question, or they'll accept one that's blatantly wrong because it matches their personal bias, or any number of other things I've seen happen on other sites.
Bearing that in mind, I don't agree at all with "So if I ask something, and an answer is incomplete or even inaccurate, but still helped me understand the issue or solve my problem, it should be accepted."
An accepted answer will always be the first answer to the question that a user sees (because the system floats accepted answers to the top of the list), so the accepted answer should be the best and most complete answer to the question asked.
Accepting an incomplete answer that vaguely sent you in the direction of the right resource rewards the person who wrote the answer (Good: They did help you), but it doesn't help the next person who stumbles across your question, reads the accepted answer and doesn't have the same luck with Google in finding the answer.
Accepting an inaccurate answer is even worse, as it may misinform people who don't do follow-up research and thus runs the risk of someone citing the inaccurate information ("I got it from the Aviation stack exchange site") and making the whole site look bad for handing out wrong information.
Rather than accepting an incomplete or inaccurate answer it's preferable to upvote the helpful answer (if it's also an accurate answer) and then either:
Edit the answer to be complete & accurate and accept it.
This ensures the person posting the original answer gets the Fake Internet Points for an accepted answer.
Post a new, complete, accurate answer based on your follow-up research.
This deprives the person who posted the original answer of their Fake Internet Points, but ensures that the first answer people encounter will be complete and accurate, to the best of your knowledge and research abilities.
What's the etiquette here, post is now voted not-useful, do I leave it or delete it?
I would suggest trying to clarify it, see if that leads to better reception. Hard to understand what you are asking right now. $\endgroup$