The pattern I've seen is that AWS makes sense for startups, then you hit a point where you need a hundred hosts in a couple of data centers and you can do that

The pattern I've seen is that AWS makes sense for startups, then you hit a point where you need a hundred hosts in a couple of data centers and you can do that more cheaply with raw hardware and a small team to handle it. Then you hit a point where you need thousands or tens of thousands of servers in multiple countries and you need to handle legal and logistic concerns and it's better to be in AWS (or GCE or whatever) again. That's the reason I've heard that Netflix and a lot of the other big companies are there.