When it comes to software testing, people disagree quite a bit. Some argue vehemently for a particular point of view, while others consider that very position nonsensical. For example, the "zero defects" crowd generally thinks the "good enough quality" crowd is out to lunch -- and vice versa. The different camps have different pictures in their heads, different frames of reference and implicit assumptions. A big part of what's important in debates about software testing (and, by extension, software quality) is what goes unsaid because the speaker considers it obvious.