Wikipedia lacks the necessary coverage  One of the major problems with Wikipedia is that it has very patchy coverage. Traditional reference sources provide consistent coverage over the whole field of knowledge, with priority given to the most important topics in terms of space and thoroughness of treatment. By contrast, Wikipedia has very detailed coverage of topics in which its main contributors are interested, but weak material on other, much more important issues. [1] Thus, there is, for example, much more on the imaginary language of Klingon than there is on the life and philosophy of John Locke.  [1] Why Wikipedia is not so great. Retrieved November 14, 2004, from Wikipedia.