On-demand production does not remove inventory, setup, quality, capacity, or customer-promise risk; it relocates those decisions into a faster operating system that must be measured end to end.
Build a launch backward from evidence and customer promises, with product, compliance, content, production, commerce, fulfillment, and human approval gates on one critical path.
A low-cost button, zipper, label, elastic, cord, or package can sit on the critical path when specification, color, minimum, approval, testing, production, transit, receiving, and change control are not planned together.
Material and sewing minutes matter, but setup, run size, lawful loaded labor, efficiency evidence, rework, quality, packing, overhead, and change control determine whether a cost view is usable.
Small lots reduce the number of units available to absorb setup and defects, but they do not justify an invented sampling shortcut. Prioritize specification, first piece, change control, risk, traceable inspection, and qualified disposition.