Why don't academics write in Wikipedia?

Since several years ago, Wikipedia is being widely used by academics. As a theoretical physicist, I often use it as a quick reference for mathematical terminology and results. Wikipedia is useful in spite of its many gaps and flaws: there was no general article on two-dimensional conformal field theory until I started one recently, the article on minimal models is itself minimal, and googling conformal blocks sends you to a discussion on StackExchange, since there is nothing on Wikipedia.

The paradox is that many academics see these gaps and flaws in the coverage of their own favourite subjects, yet do nothing to correct them. Let me discuss three possible reasons for this passivity: fear of Wikipedia, lack of time, and laziness.

The jungle outside the ivory tower

 

Attracting and retaining academic contributors has long been recognized as a challenge by Wikipedians, to the extent that there are guidelines on how to do it.