Search engines are interesting creatures. How does a database decide what is the ultimate authority on the subject? Google for instance uses PageRank - an equation that takes alot of factors into account. In essence it looks to see what is the page that is most LINKED to on the internet and that basically establishes its importance. It also takes into account how many links link out of the page. A page that exists as just text for instance with no links, would have very low rank, even if a good deal of people linked to it.
In other words, Google finds the most popular pages, not necessarily the pages that have the best or most accurate information.