Why does IBM keep separate branding for Watson and Bluemix AI? It seems like most "Watson-in-the-field" deployments are leveraging the Bluemix pre-baked models

Why does IBM keep separate branding for Watson and Bluemix AI? It seems like most "Watson-in-the-field" deployments are leveraging the Bluemix pre-baked models for specific workflows like document classification, transcription, etc. Seems like they'd better align the marketing and the offering if Bluemix was the "Watson gateway" so to speak. They could still sell and market Watson as the custom consulting they do, with Bluemix branded as an entry point to basic Watson functions. There's some speak of this in their product copy, but it could probably be more obvious.