Why do sclerenchyma tissues become dead on maturity?

Sclerenchyma tissues become dead at maturity primarily because their primary function is to provide structural support and rigidity to plants. They are characterized by thick, lignified cell walls that are often too rigid to allow for metabolic processes, leading to cell death. This dead tissue contributes to the strength and durability of plant structures, such as stems and seed coats, enabling them to withstand various environmental stresses.