Quality
I had a class of software testers. I was to teach them in Java.
Just for fun I asked them about the definition of Quality.
Testing is as many of you know QA or Quality Assurance. To my surprise very few of my students knew the definition of it which was surpricing as they were at the end of their two year education.
I got answers like “something good”, or similar. One student was exceptional, he knew, not only, the definition of Quality, but also that quality is something you can measure or test. “Good” is not testable and you can’t verify it, so it isn’t quality.