Wikipedia is always being edited, and thus there is a good chance that any given error will eventually be discovered and corrected — that is, to be discovered and corrected on the Wikipedia website, wikipedia.org. However, since Wikipedia content can be copied freely, snapshots of Wikipedia entries are often taken and posted by third-party content providers. Therefore, any given Wikipedia error will likely continue to exist, somewhere on the Internet, indefinitely (and, obviously, long after it has been corrected on the Wikipedia website itself).
For example, this sentence once was part of the Wikipedia entry for the Smashing Pumpkins:
To give them indie credibility, Virgin matched the band with Sonic Youth producer Butch Vig and released their 1991 debut album Gish on Virgin subsidiary label Caroline Records.
The first part of this sentence seems to have been entirely made up, which probably explains why it is no longer part of the entry on Wikipedia’s site.* Vig says on Vieuphoria: “The first thing I worked with [Smashing Pumpkins] on was a Sub Pop single. Jonathan [Poneman] from Sub Pop called me up and said, ‘There’s this band from Chicago that is awesome and you’ve gotta work with them.’” Vig then produced the Pumpkins’ single “Tristessa”, which Sub Pop released in December 1990. Shortly thereafter, the Pumpkins signed with Caroline. Vig first produced Sonic Youth in March 1992.
However, you can still find the erroneous sentence today on a variety of third-party sites that copied the Wikipedia entry at that time. A lot of these sites are weird and spammy, but they do find their way into search results. My guess is that they still get read, and believed, fairly often.
*It doesn’t explain, however, how the sentence came to be there in the first place. That is not the subject of this post, but, generally speaking, “where does this stuff come from?” is one of the driving questions behind this blog…