[Jlagreen]

AWS for Amazon was a logical step because who is AWS largest customer? Amazon of course.

If you build large eCommerce like Amazon then of course you need huge IT infrastructure for it. Amazon was kind of forced to build the IT infrastructure and in that process Bezos saw another business opportunity because not every smaller company can easily build large IT infrastructure but many companies need it. And just as AWS built "SW services" for Amazon eCommerce it also became the foundation of the cloud business.