If you’re going to have a complicated story you must work to a map; otherwise you’ll never make a map of it afterwards.
Tackling a test retrofit on legacy software as your first attempt at automated unit testing is the last thing you want to try, as it is sure to discourage even the most determined developers and project managers.
Refactoring ist pain management.
Duplicate code is the long grass in which bugs thrive.
And there is maintenance, the ugly cousin of software development.