Final answer:
A quality focus in software engineering is about ensuring that a product has attributes that satisfy both functional requirements and non-functional desirable characteristics such as reliability and usability. Criteria and constraints are critical for evaluating the quality of a design.
Step-by-step explanation:
A quality focus in the context of software engineering emphasizes the importance of developing a product that not only meets functional requirements but also has desirable characteristics such as reliability, maintainability, and usability. The quality of a design is often evaluated through the identification of criteria and constraints. Criteria are measurable attributes that allow for the comparison of different designs, helping to determine which is superior. Constraints are necessary conditions that the design and process must satisfy, like budget limits or regulatory standards. For example, if engineers don't test prototypes adequately, it may lead to a quality issue that could have been identified with proper criteria and adherence to constraints.