There is unfortunately a bias against introversion in many companies, which explains why some don't bother to try. (Recent article: http://www.economist.com/news/business-and-finance/21706490-...)

Having said that I agree also that there are also trust issues. Forming trust is a hard thing.

It's a shame, because programming (from at least my perspective) is one discipline, where the quality of work is so much higher when you are "in the zone" and can concentrate on a single task without interruptions.