What's wrong with re-solving an existing problem? Isn't that the entire idea of "fearless refactoring" that several process models use to mitigate reliance on/c

What's wrong with re-solving an existing problem? Isn't that the entire idea of "fearless refactoring" that several process models use to mitigate reliance on/complacence with archaic systems? I don't think "it's been done before" has ever in the history of progress been a good reason for something to not be reexamined and made better or easier to use.