What comes first the chicken or the egg? OR, in this case S/4HANA or BW/4HANA!
Honestly, it depends and that is the decision many organizations are struggling with. The answer should be primarily driven around where your bigger pain point is. Are you struggling with timely insights into the day to day operations of the business? Or are you struggling with the strategic analytics associated with the overall results of your organization, or both. I will briefly address some key factors below that should start the discussion.
In the case of S/4HANA you have real-time operational data and a new Fiori tile based user interface. You also get HANA in-memory speed for your data and a simplified table structure. S/4HANA includes an embedded BW 7.5 system, and with that gives the capability of embedded analytics. Because there is a recommendation of limited persistent data, it gives you specific capabilities (think no historical data). Most global companies however, often run multiple instances of SAP ERP and other systems making a move to a single S/4HANA system a very daunting and time consuming task that must be meticulously planned out.
On the other side is BW/4HANA, this is now a true Enterprise Data Warehouse (EDW) utilizing HANA and all the in-memory advantages. BW/4HANA provides the ability to perform strategic analytics. In a data warehouse you are not focused on the daily operational data needs and so you can refocus the persistent data. Now with data tiering in BW/4HANA you can easily move data between hot, warm and cold storage. Data tiering is important because storage of hot data (persistent) is more expensive; warm data (extension nodes with less stringent performance expectations) is less expensive and cold storage (stored on disk and less frequently used) is least expensive. BW/4HANA through its new streamlined structure makes accessing the data much easier and faster. Add the ability to bring in Big Data and unstructured data plus Hadoop and now you have the making for strategic analysis.
So, both SAP/4HANA and BW/4HANA are SAP’s planned future direction and going to either is the right choice, it just depends on what your biggest needs are. Both are available on premise or in the cloud. In many cases though, I think the right answer is to start with a move to BW/4HANA.