Internal and External Quality

In Extreme Programming Explained, Kent Beck writes, “There is a strange relationship between internal and external quality. External quality is quality as measured by the customer. Internal quality is quality as measured by the programmers.”

He goes on to explain the human effect on quality: “If you deliberately downgrade quality, your team might go faster at first, but soon the demoralization of producing crap will overwhelm any gains you temporarily made from not testing, or not reviewing, or not sticking to standards.”