Print on demand

Print on demand (POD) is "a printing technology and business process in which products are produced only after an order is placed, rather than in advance in bulk," which lets a publisher sell "without maintaining an inventory of finished goods in advance." For books it "could only develop after the beginning of digital printing": press-based methods made single copies uneconomical, and digital presses removed the setup cost that forces a big print run.

The author economics the article gives: "the initial investment required for POD services is less than for offset printing," with "greater financial return per copy than royalties paid by conventional publishers," but POD companies "typically do not invest in marketing, unlike conventional publishers," so promotion stays with the author. No inventory risk plus no gatekeeper is what makes the serialize-then-collect route of self-publishing viable, and every copy printed is a copy already ordered.