No credit card required
Many requirements map well from design to implementation code.
Other requirements have little correlation to design and implementation; the form of the requirement differs from the form of the design and implementation: the problem of orthogonality.
Object orientation and use cases can help alleviate the problem of orthogonality.
Use cases drive design by allowing all stakeholders to examine the proposed system implementation against a backdrop of system uses and requirements.
Good system design is not necessarily optimized to make it easy to see how the requirements are implemented within the implementation.
We have been building complex software systems for over 40 years. And yes, our industry ...