Simple Workflow was pushed hardcore on everyone inside and outside Amazon for years. It's not a very useful service, but they had huge marketing. Obvious to me is their managers thought that if everyone used SWF, then SWF managers would become very powerful because it was supposed to be bigger than any one organization and cross-organizational. I imagine virtually everyone at Amazon has had SWF pushed on them by their managers as a silver bullet technology that will bring their service and thus manager in to the Amazon high inner cabal and make them very powerful.
In reality it was a task scheduler with some logging and metrics thrown in which awkwardly tied user's individual code builds to a third party service where they had to be registered and externally reference for every build. Virtually all SWF functionality was in the client library, not the service which was just a data store and API.
Other cool kid services that managers wanted to force teams to use included dynamodb, kinesis, lambda, etc.
