Because Web readers like short pieces, that's why. I want to take a second whack at this, and expand on the material I wound up cutting. Consider this a defense of Amazon, a rebuttal of what I wrote earlier, if you will, penned on behalf of Amazon by yours truly. Amazon, of course, had absolutely no input into this, but they're smart people, and if they had the chance, I think they'd try to counter my two points with these answers.
Trouble is, they'd be wrong.
The ability to turn on a dime, to change the business virtually in midair, is a hallmark of a well-run Web operation. Speed, after all, is one of the most valued characteristics of a Web-business management team. Managing in the Web Era, especially managing Web businesses, is a midair act, with few fixed points of reference and no eternal verities. Sure, change fast, rejigger the business, reorient. Set new priorities.