WIth some TV shows there are plenty of character that although they were originally introduced as the antagonist or "villain" of the show, they go through a development that involves them trying to change their ways or become better people as the show goes on.
While some people grow to love those characters that come along way from who they used to be, or are just very impressed by their development and mainly like them for being more interesting and dimensional. There are still those that are hostile towards them, and feel their "redemption" was half-assed or only became "one of the good guys" because of their popularity.
Netflix's Sex Education I found did a great job with how well they wrote Ruby, Adam and Michael Groff (who all played antagonistic roles in the first second of seasons of the show), but as they are given more screen time. They become the best characters as they are slowly learning to become better versions of themselves.
Who is a character that you think had a redemption arc that was done right?