Yup. And of course, you are looking at the English Wikipedia, which is the most-developed language version of Wikipedia. Yet Wikipedia claims to be available in over 280 languages, when in many of them, coverage is really, really rudimentary. See e.g. the
"Mind the zombies" slide from a recent Wikimania presentation – basically, only 125 language versions of Wikipedia have more than 5 editors. The others are, to all intents and purposes, dead.
Note also that even English Wikipedia contributor numbers (as opposed to reader numbers, which are immense) are really quite small. (Someone else has pointed this out above.) If you look at
this table, you'll see that there are only about 3,000 regular editors in the English Wikipedia, i.e. people who make more than 100 edits a month (i.e. about three a day). That number has shrunk considerably over the past few years, from a March 2007 high of 4785. At the same time, of course, the number of articles continues to increase constantly (now at 4.6 million). There are fewer contributors, and more articles to be watched over.
So Wikipedia has many articles that it does not have the (wo)manpower to curate adequately. In the early days, of course, everyone thought that "eventually" all these articles that someone started would become little masterpieces, but it's becoming clear that this will not happen. Little-watched biographies in particular are a problem, as the only people interested in them are usually the subjects and/or people who hate them for some reason, so they turn either into puff-pieces or hatchet jobs, with no one really noticing (there are well over half a million articles that no one has on their watchlist). Yet they are the top search hit when someone Googles the name online.