SAP HANA was released as a work in progress. Tenants could leverage the increased speed of the HANA database immediately, but had to wait for the updated SAP S/4HANA applications to be released. Each release has allowed applications to more fully harness HANA, creating new, compelling reasons to migrate for a range of use cases.
With the S/4HANA 1709 release, SAP has taken yet another step toward creating a complete product, with substantial benefits over Suite on HANA for most use cases. As with any ERP software, there will be future improvements and innovations, but at this point upgrading to S/4 is a worthwhile investment for nearly every landscape still on SAP ECC or Suite on HANA.