The FDA recalls the Kugel Hernia Patch because the plastic memory coil that was used to open it is dangerous as it has broken and led to injuries in many patients. The hernia patch is placed over the layer of skin that insulates the gastrointestinal tract known as the peritoneum; therefore, the broken coil can cut into the peritoneum and the bowels, stomach, or intestines.
Cutting through the peritoneum and cuts into the bowels can cause gastrointestinal or septic leakage into the peritoneum and outside of it as well. This can and will cause a serious infection, renal failure, peritonitis, and a multitude of other rapidly progressing medical problems.

FDA Product Recall Site for Kugel Patch
National Library of Medicine Article on Kugel Patch Procedure