Critical to Quality (CTQs) focuses on fulfilling customer:

Critical to Quality (CTQs) are key measurable characteristics of a product or service that must be met to satisfy customer requirements and expectations. Focusing on fulfilling customer requirements emphasizes understanding what the customer truly needs and values; this ensures that the final product or service meets their expectations for quality and performance.

In the context of Lean IT, identifying CTQs helps prioritize areas for improvement and drives the establishment of clear quality benchmarks. This alignment with customer requirements enables organizations to deliver high-quality experiences, resulting in increased customer satisfaction and loyalty.

While customer wishes, feedback, and complaints are important aspects of understanding customer perspectives, they do not necessarily capture the specific criteria that define quality in a measurable way. Requirements capture the explicit needs and standards that must be achieved to satisfy customers, making it the most appropriate focus for any quality-driven initiative.