For me, the reason is sites like Stackoverflow which have answers to just about everything. Although I like to use multiple sources and so I do click on links to forums related to my search query, but usually sites like SO already have a good enough answer. And because of the traffic, you can get answers extremely fast on SO compared to forums so it's perfect for people who don't care about being in a community/forum environment. Maybe sites like SO are spoiling us for near instant answers. Who has time to make friends/relationships when you can find the answer right away, right?