Many factories do not have time to take products off the line, mark them one by one, and put them back again. The packaging line is already running. Bottles, boxes, bags, pipes, caps, labels, or parts move continuously. If coding depends on manua ...

Some products are difficult to mark because the surface cannot accept too much heat. Thin plastic may deform. Transparent glass may crack or show rough edges. Cosmetic packaging may look dirty if the mark is burned too strongly. Electronic parts ...

A packaging factory usually has many small problems that outsiders do not notice. The carton surface is not always flat. Paper bags absorb ink differently from coated boxes. Wooden products may have natural grain, dust, or moisture. Leather tags ...