An interactive retail display is an in-store screen the shopper can act on (touch, scan, or gesture) rather than only watch. The interaction usually does one of three jobs: extend the range beyond what fits on the shelf, answer a question that would otherwise need staff, or capture something the retailer wants (a signup, a preference, a basket).
It earns its place where the physical store has a limit the screen removes. Endless-aisle displays for sizes not stocked, configurators for products with too many variants to merchandise, and queue-side ordering are the cases that survive contact with a P&L.
The caveat: the display is competing with the phone already in the shopper's hand, and usually losing. A screen that shows the same catalogue the customer could browse while walking gives them no reason to stop. The interactions that work are the ones the phone cannot do: knowing what is in this store right now, printing something, unlocking a fitting room, moving a physical mechanism.
Second, budget for maintenance from day one. A touchscreen in a retail environment is handled thousands of times a week and looks neglected quickly; one dead unit on a shop floor does more brand damage than the working ones repair.