A monolith can have beautifully organized packages and still be a nightmare to maintain.

You open the project and see folders called orders , billing , and inventory . Everything looks neatly separated. But the moment you investigate the dependencies, the real picture emerges.

Orders imports Inventory's internal repository. Billing relies on implementation details from Orders. A small change in one feature unexpectedly affects several others.

The problem isn't necessarily that the application is a monolith.

The problem is that its module boundaries exist only in the folder structure, not in the architecture.

Moving to microservices will not automatically solve those dependencies.…