This essay focuses on the evaluation of health programs and services, emphasizing the subjectivity emerging from the evaluation process. The text is a theoretical construction that targets the various meanings of evaluation, the influence of the positivist paradigm on the field of health program and service evaluation, the polysemous nature of the term "quality", and its close overlapping with subjectivity. In addition, the authors highlight the importance of studies that incorporate the perspectives of social actors into the evaluation processes, recommending qualitative social research methodology as a productive instrument.