Screen printing: colour passes are the real capacity
A screen printing line is not constrained by garments, it is constrained by passes. A one-colour one-location print consumes one pass per garment; a three-colour two-location print consumes six; a six-colour design at two locations consumes twelve. On a four-colour carousel, a twelve-pass design is roughly six times the press time of a two-pass design, and that ratio is exactly what the quoted per-unit price is reflecting when a low-volume and a high-volume quote for the same artwork differ so much. The practical ceiling locally is around 1 500 to 2 000 garment-prints per garment-position per working day on a single four-colour carousel at realistic efficiency, which means a 2 000-unit order with a six-colour design can consume an entire machine for a day and a half before the second production step even starts. Above roughly 3 000 units on a complex design, the local line stops being economical and a second pass or an overflow subcontract becomes the honest answer. Buyers who reduce a six-colour back print to a two-colour front print and a single-colour sleeve print get the same visual effect at a fraction of the pass count, and that redesign is usually available if it is raised before prepress rather than after.