Sewing problems consist of issues with stitch formation, seam pucker, and fabric damage at the seam line. Problems with stitch formation include slipped stitches, staggered stitches, unbalanced stitches, variable stitch density, and frequent thread breakage. These issues are caused by improper needle size/tension, thread size, and machine adjustments. Seam pucker is caused by unequal fabric stretch, shrinkage differences between fabrics, excessive thread tension, and thread/fabric properties. Fabric damage occurs from mechanical damage or heat damage by the needle, which can be addressed by selecting the proper needle size/shape and machine settings.