Which product quality dimension refers to the probability of a product performing its intended duty without failure for a given period?

The dimension of product quality that pertains to the probability of a product performing its intended function without failure over a specific period is reliability. Reliability indicates how consistently a product will operate as expected under normal conditions and over time. It emphasizes the importance of the product’s performance stability, ensuring that it provides the intended service without defects or breakdowns during its lifespan.

In contrast, the other dimensions of quality address different aspects: functionality refers to the features and capabilities that a product offers; usability involves how easy and intuitive a product is for users; and maintainability relates to how simple it is to perform repairs or maintenance on a product when it does fail. While all these dimensions contribute to the overall quality of a product, for this specific question, reliability stands out as the key factor concerning performance consistency over time.