Gray Balance is critical because it acts as the primary diagnostic tool for the entire CMYK color reproduction process. When the Cyan, Magenta, and Yellow inks are perfectly balanced to create a neutral gray, it guarantees that all other colors on the sheet are also accurately reproduced and won't shift. Print supervisors use standard control strips (gray patches) on the plate for visual confirmation. For numerical accuracy, they rely on densitometers or spectrophotometers to measure and maintain the balance based on standards like ISO 12647. Maintaining this balance minimizes color drift and reduces waste.