A marketer may, for example, suspect that there is a correlation between the distance from the customers’ home addresses to your local department store and lifetime value. In order to prove or disprove this hunch, you want to be able to quickly calculate customers’ distance from their nearest store, maybe banding them into meaningful categories (e.g. 0-15 miles, 15-30 miles and 30-45 miles). You may want to be able to show these correlations in an analytic cube or visualisation.
Here are some common use cases for calculating new data from your first-party data.
Date and time-based derivations
These may include, for example:

Anniversary calculations (e.g. six months or 1 year from first purchase)
From a sequence of historical purchases, calculate what the Next Best Date (or time window) is for contacting a customer
Calculating the average number of days between receiving a marketing communication and making a purchase, or between a call to the service centre and cancelling a contract.