What fundamental advantage of the square-bottomed bag did Margaret Knight recognize regarding retail efficiency?

The bag could stand upright for easier filling and storage

Knight's core insight centered on the creation of a three-dimensional, self-supporting container from a previously flat, awkward piece of packaging. The crucial advantage this offered, particularly in busy retail environments like general stores, was that the bag could stand upright on its own. This capability eliminated the need for a clerk to use an extra hand to physically hold the bag open while filling it with merchandise. This seemingly minor geometric enhancement directly translated into increased packing speed, reduced errors in transactions, and improved storage presentation, embodying an early, powerful example of supply chain optimization achieved through intuitive industrial design.