Ask HN: Do you work in a company that will fire you for average performance?

I heard in NPR today that Netflix fires people that are average and only keeps those that are exceptional. Does any one have any experience working in such a company? When I heard about netflix, it seemed like life would be very stressful if you always have to worry about getting fired. But on the plus side, you get to learn a lot and work with exceptional people, which is a great way to learn. ANy experiences or opinions?