Good, better, best
Turns out that most people use only a fraction of the space on their iPods: Objects in Ears Are Not as Full as They May Appear – New York Times.
No surprise, of course.
We don’t buy a bigger iPod because we need a bigger iPod. We buy one because we identify ourselves as the kind of person that doesn’t squabble over a few bucks when it comes to buying the best. And that’s the kind of person who buys a new iPod when her old iPod works just fine.
Businesses do the same thing (how much free space on your hard drive at work?) (how much cheaper could the HR guys have found an office chair for you?).
Nobody buys "best" in everything in their life. But in every category that’s not a commodity, somebody is buying "best" because they want to, not because they need to.