Only when you can access the  90% of historic data that is inaccessible today- the unstructured data held in emails, letters, scanned documents, video, photo diagrams.

Data silos in core systems of record plus the alarming number of different BI tools. Ingest and analyse those before attempting to move on to external sources.

Document management  systems are usually not a help so look at online platform tools like 360Retrieve

Of course, it's not good accessing it unless you can join this unstructured data with the structured data already analysed. Again, if you want to see a working solution go to 360Insight.