Tue Nov 29 00:12:57 HKT 2016
"They build their own infrastructure for performance, reliability, and cost control reasons. By building it themselves they never have to say Amazon went down because it was company X's fault. Their software may not be more reliable than others, but they can fix, debug, and deployment much quicker than when working with a 3rd party."
Shel Kaphan - http://www.infoq.com/cn/articles/talk-with-amazon-shel-kaphan
(google search) (amazon search)