We have a legacy system (Wins + DB2), which stores all our data.
For reporting purposes (from SQL), we need to analyze data. We use it for making decisions, for example, if we want to display data elements in our reports based on if a column ever gets a value entered by user or what are distinct values that we are receiving for transformation purposes.
We use it to check patterns, like zip code, state codes, and phone numbers.
We also check data value frequency for business decision in mapping from one system to another.