The statement is incorrect because it presents an absolute ("never") that is not practical or aligned with comprehensive quality assurance principles. While baselines founded on objectively measured data (e.g., defect density, CPU usage) are highly desirable for their repeatability and lack of bias, they cannot capture all critical aspects of software quality.

Certain essential quality attributes, such as usability, user satisfaction, and perceived performance, are inherently subjective. To measure and improve these areas, it is necessary to establish baselines using subjective data, typically gathered through structured methods like user surveys (e.g., Likert scales, Net Promoter Score), expert reviews, or focus groups. The key is not to avoid subjective measures but to collect them through a consistent, well-defined process to ensure the resulting baseline is as reliable as possible for future comparisons.

The statement "True" would be incorrect because it dismisses the validity and necessity of measuring qualitative and user-centric aspects of a product. A quality program that ignores subjective feedback is incomplete, as it overlooks the end-user's perspective, which is a critical component of overall product success. Prohibiting the use of subjective data for baselining would mean that crucial goals related to user experience could not be formally tracked or improved against a starting point.

1. Basili, V. R., Caldiera, G., & Rombach, H. D. (1994). The Goal Question Metric Approach. Institute for Advanced Computer Studies, Department of Computer Science, University of Maryland. (Also published in Encyclopedia of Software Engineering, pp. 528-532).

Reference Point: The Goal-Question-Metric (GQM) paradigm, a foundational concept in software measurement, demonstrates that the metrics chosen depend on the specific goals. If a goal is "to improve user satisfaction" (a subjective concept), the corresponding questions and metrics will necessarily involve subjective measures. These measures are then used to establish a baseline from which to track improvement. The GQM framework validates the use of metrics derived from subjective viewpoints to satisfy specific quality goals.

2. Fenton, N. E., & Bieman, J. M. (2014). Software Metrics: A Rigorous and Practical Approach, Third Edition. CRC Press.

Reference Point: Chapter 2, "Software Measurement," and Chapter 11, "Measuring and Analyzing Customer Satisfaction." The authors distinguish between objective and subjective measures, noting that both are necessary. They explicitly discuss methods for measuring customer satisfaction, which "is by its nature a subjective attribute," and how to use the resulting data to create meaningful benchmarks (baselines) for process improvement.

3. University of Toronto, Department of Computer Science. (Courseware for CSC444H1/2405H: Software Engineering).

Reference Point: Lecture materials on "Software Quality and Metrics" often discuss the need for a balanced set of metrics. They explain that while objective metrics like code complexity or defect counts are vital, they do not provide a complete picture. Metrics for usability and user satisfaction, derived from subjective sources like surveys and heuristic evaluations, are presented as essential components of a comprehensive quality assurance strategy and are used to set baselines for user-centric improvements.