Has anyone had a success story in rewriting an application?

I see many cases where people will just push off rewriting or doing an application better, and I have not personally seen this play out in any job I have worked at. All of my experience has been with older applications has just been trying to get the new feature to work within the system constraints of the old system. I know its a bit of a joke to "rewrite it in rust", and I get why. Engineers typically don't have a business or product rational for why a rewrite is better, its more of something that they want to do in order to better understand a complex system. However I'd love to know of any success stories.