Why does the narrator want to erase the memory on the scarlet letter?

The narrator never states that Hester wanted to erase the memory, only that the memory became something else..... a symbol of sadness and yet a symbol of remembrance.

Never afterwards did it quit her bosom. But, in the lapse of the toilsome, thoughtful, and selfdevoted years that made up Hester’s life, the scarlet letter ceased to be a stigma which attracted the world’s scorn and bitterness, and became a type of something to be sorrowed over, and looked upon with awe, yet with reverence too.