Contract work has been reminding me that legacy systems are rarely just old code. They are old promises. A strange branch in the flow might be a merchant exception. A confusing column might be a pricing rule from three business models ago. A widget that feels awkward might still be carrying the shape of a real customer workflow.
That does not mean the system should be left alone. It means the first job is translation, not judgment. Before changing a legacy path, I want to know which product memory it is preserving and who still depends on it.
Good modernization is not the act of replacing messy code with prettier code. It is the act of separating accidental complexity from earned complexity, then preserving the business truth while making the software easier to change next time.