growing a sapphire crystal is difficult, and like silicon chips, the bigger the surface area, the chances of defects goes up exponentially. Additionaly, ading $

growing a sapphire crystal is difficult, and like silicon chips, the bigger the surface area, the chances of defects goes up exponentially. Additionaly, ading $200-300 to the BOM to make your product last longer is a bad idea, since each broken screen is usually a sale or a $500 repair bill. simple economics.