It is true that Hester Prynne's actions, as well as those of Arthur Dimmesdales's influenced a number of changes to take place in the novel The Scarlet Letter.
Unquestionably, the most significant change is Hester Prynne's own transformation, from a feeble woman, into a strong one. This is because Hester is the only one of the characters whose own story completes a full circle that goes from pain, to shame, then resignation, acceptance and, finally, closure.
Hester's time in prison made her a stronger woman. She took the scarlet letter, which was meant to be a symbol of humiliation and shame, and transformed it into a token of separation which, later on, is seen as a symbol of distinction. Hester goes as far as stating in Chapter VIII, "The Elf Child and the Minister", that the scarlet letter has actually made her into a better person
...this badge hath taught me,—it daily teaches me,—it is teaching me at this moment,—lessons whereof my child may be the wiser and better, albeit they can...
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