Good software deserves active testing. The activity of testing does not stop with the work of understanding what the software does. It must be completed by the work of criticism, the work of judging. The undemanding tester fails to satisfy this requirement, probably even more than he fails to analyze and interpret. He not only makes no effort to understand; he also dismissed a product simply by putting it aside and forgetting it. Worse than faintly praising it, he damns it by giving it no critical consideration whatever.

Huh? Harsh words. Let’s discuss them in the light of testing vs. checking.