At the beginning of StackOverflow there was a very strong opinion held by the founders, particularly Jeff Atwood, that the longevity of a site was determined by the signal to noise ratio. The emphasis at the outset was to eliminate as much noise as possible. Automated systems were put in place that went way too far, in my opinion. The whole Chat system was put into place to get comments off the main pages. Even though Jeff Atwood hasn't been at the company for years, the philosophy still seems very entrenched.