Government. It has a high barrier to entry (win an election/revolution) and a high consumer switching cost (move far away, get a new job, learn a new language). If the governing industry were more competitive, I think its quality of service would be better.

The Peter Thiel-funded Seasteading Institute is trying to decrease the start-up cost and the consumer switching cost. Paul Romer has another approach with the Charter City proposal he's advocating.