This was not exactly a Jeff Bezos mandate but the result of an engineering brainstorm. The mandate came more out of a "how to scale Amazon for the next decade"

This was not exactly a Jeff Bezos mandate but the result of an engineering brainstorm. The mandate came more out of a "how to scale Amazon for the next decade" discussion. In large companies, one where distributed/independent teams are as important as distributed systems this ended up being the only way to operate. Initially, during the good old days of Amazon, there was what you'd call a single datawarehouse. It made sense initially for every system that processed an order to access the data by querying that data warehouse—this meant that the processes would be distributed (different services), while the data would be centralized. It also meant that any change to the way the data is stored in the datawarehouse meant deploying code to a hundred places. The most important problem that this addressed was however different. A centralized datawarehouse meant that every customer request bubbled up into N queries to the datawarehouse (where N is the number of services that needed access to the data—billing, ordering, tracking...). The mandate summarized in one line would be this—"the data is the one that should go to the services, not the other way round." Voila, microservices.