Many sources for Wikipedia articles refer to Wikipedia without citing it. Many journalists will work from Wikipedia, and most of Wikipedia's sources are journalistic articles. It happens to be that often this isn't noticed because the information obtained this way is true and uncontroversial. Citogenesis only documents examples where, by bad luck, the result is untrue information.
No citogenesis is present regardless of whether the information is "true". The concept of "truth" on wikipedia doesn't have much weight, mainly because it would be impractical, out of scope and original research to determine truthfulness.
