I've come to almost the same conclusions as the author. - The first tribe is mostly coming from Maths background, their favorite performance measure is the big

I've come to almost the same conclusions as the author. - The first tribe is mostly coming from Maths background, their favorite performance measure is the big O notation. - The second tribe is coming from Physics/Engineering background, their favorite performance measure is expressed in SI units, most often a duration. - The third tribe is coming from everywhere else, and their favorite performance measure is customer satisfaction, or in other words dollars.