The loop stitching method is very different from ordinary hand sewing. In the simplest form of hand stitching, the seamstress attaches a thread through the eyelet at the end of the needle, then passes the needle and thread completely through the two pieces of fabric, from one side to the other and back again. This way, the needle drives the thread in and out of the fabric, to stitch them together, and the machine needs to release the needle on one side of the fabric, and grab it again instantly on the other side. It then entails pulling all the loose threads out of the fabric, reversing the direction of the needle, and repeating all steps in the opposite direction. The process was too complicated for a simple machine to be practical, and even by hand it only worked well with shorter threads.
