When evaluating glass coatings, the most critical metric is the Hardness Level, typically measured on the Mohs scale or Pencil Hardness scale (e.g., 9H hardness). For automotive applications, prioritize Hydrophobicity, indicated by a Water Contact Angle of >110°, which ensures superior water beading and self-cleaning properties. Additionally, verify the Durability/Longevity—industrial-grade coatings should offer protection for 2 to 5 years depending on the environmental exposure. For architectural glass, ensure the coating provides UV Protection (at least 99% blockage) and Infrared Rejection (IRR) to improve energy efficiency.