Digital products depend on the collaboration of designers and developers. Designers shape how people experience a product. Developers shape how that experience becomes stable, scalable, and real. Each discipline holds expertise that the other cannot replace. Yet across product teams, even highly skilled designers and developers often struggle to work together in ways that sustain shared understanding. They exchange files, comment on prototypes, and update tickets, but the reasoning behind their decisions remains mostly private. As a result, the product begins to drift from its purpose long before anyone notices something is wrong.