Why do overcooked poultry become dry?

Overcooked poultry becomes dry because prolonged exposure to heat causes the proteins in the meat to contract and moisture to evaporate. As the internal temperature rises beyond the ideal cooking range, the muscle fibers squeeze out their natural juices, resulting in a loss of tenderness and moisture. Additionally, the fat that helps keep the meat moist can render out, further contributing to dryness. Proper cooking techniques and monitoring internal temperatures can help prevent this.