An ecommerce brand spending $80K per month on Google Shopping hit a revenue plateau. The problem was not bidding. It was a flat product group structure, no custom labels, and brand queries blended with generic traffic. This case study walks through the structural audit, the three-part rebuild (margin-tier segmentation, custom label strategy, brand and generic separation), and the ROAS recovery within 60 days. The core lesson: Google Shopping underperformance is almost always a structural and feed problem, and no tROAS adjustment can fix a broken foundation.