What makes T-Bag fascinating is the writers' refusal to let him die. He survives prison riots, manhunts, and amputations. He is the cockroach that survives the nuclear blast. In a strange way, T-Bag becomes a necessary evil. In later seasons, we see glimpses of a twisted humanity in him—a desire for family and acceptance that he is genetically and socially programmed to destroy. He is the monster the system created, and the monster the system cannot contain.
Prison Break works because it treats its characters like structural elements. Some are foundations (Lincoln), some are supports (Sucre), some are corrosion (T-Bag), and some are the engineers (Michael). characters on prison break