Why did Hester have to wear a red A on her clothes in The Scarlet Letter?

In Nathaniel Hawthorne's "The Scarlet Letter," Hester Prynne is forced to wear a red "A" on her clothing as a form of public shaming for committing adultery. The letter symbolizes her sin and the societal judgment she faces, marking her as an outcast in Puritan society. It serves as a constant reminder of her transgression and the stigma attached to it, while also evolving to represent her strength and resilience over time.