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I failed a review audit. It tells me "This post was of very poor quality, and needed significant improvements to be useful [...]". While the answer I reviewd was short, it perfectly answered the question. Since the question asked something which I found interesting, I even tried the answer myself before taking any review decission. It worked perfectly.
Looking at the whole question, there is another answer which is nicer (with a screenshot) which leads to the exact same solution. It has 21 upvotes and a comment stating: "Should be the accepted answer!" (with upvotes).
So, while the answer I reviewd is not perfect. It actually answered the question pretty well and did not deserve "downvoting, closing, or flagging as "very low quality"." as the audit suggested.
Also, since the audit did not show me that there are already other answers, I had to assume that this is the first/only answert to the question.
Did the review process trick me? I did not try to comment. So this is a different question asked there.
Should we look up existing answers when reviewing? As I learned from comments to my question, it is quite common to click on the actual question and review everything else there. Therefore it is an important question wheather this sould be the expected standard or not. Unfortunately, this is not answerd there either. Furthermore I argue that it should not be standard, but that the review process should present all relevant information. This is also in line with the policy that a good answer should provide all information needed instead of linking to an external source.