1) High-availability with minimal downtime (seconds)
2) I18N readiness & L10n language packs
3) Scale on the order of 10000 or 100K
4) Guaranteed delivery of Alerts and Metrics
5) Easy Deployment and configuration - where the first step is NOT download and deploy Redis and configure it.
Make no mistake I love open source offerings but having worked in this domain for a while, Enterprise software becomes complicated to solve complicated problems with minimal intervention by users - not every IT shop has super-duper DevOps ninjas who Crunch Machine Learning Pardigms for breakfast.