Welcome to the Wikipedia questions thread for the week of July 22, 2018!
Please use this thread to ask and answer questions related to Wikipedia and its sister projects, whether you need help with editing or are curious on how something works.
Note that this thread is used for "meta" questions about Wikipedia, and is not a place to ask general reference questions.
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New content keeps getting added to Wikipedia all the damn time. It's always under construction. I wonder what it would take to complete Wikipedia.
So, what would it take to complete Wikipedia?
Mine was in the mid-2000s, not long after I started editing Wikipedia. I came across an article with wrong information in it. Not just wrong, but dangerously wrong: many people each year die or become seriously disabled because they don't follow advice on how to use a particular thing.
(I don't want to say here what the thing is because I like to keep my Wikipedia ID separate from my Reddit ID.)
I corrected the wrong info, but had trouble adding a suitable reference because I could not find anywhere on the Internet an explicit statement on how to use this thing correctly. So I fudged a couple of references to some online resources from which one could - at a stretch - infer how to use the thing correctly, and left it at that. I checked in to the article from time to time and my correction was still there, and gradually forgot about it.
Many years later I looked at the article again and discovered that my correction had been removed, with an edit summary something like "not in sources given". This was of course technically correct: my original fudged references didn't explicitly state the right way to use the thing.
So, what to do? I could have just reinstated my original correction, but it would have simply been removed again. The only thing was to try to find a better source, so I started to Google. I was in luck: I quickly found several new sources giving explicit advice on how to use the thing correctly.
However, I couldn't simply reinstate my original correction. Why not, you may ask. Well, the new sources all used the same wording as my original correction, so if I reinstated my original wording, it would have been thrown out as plagiarism on the grounds that my wording was the same as in these new sources. You see, these new sources had simply lifted my own wording when providing safety advice for the thing: they themselves (one of them a government-funded body) had plagiarised Wikipedia.
So I reinstated my correction, but paraphrased my original wording so it wouldn't be deemed plagiarism, and used the new sources as references.