I guess that the cropped look originated from the lack of materials or the stages of minimalism i.e., the 90's were it wasn't trendy what you wore but what you didn't wear. Fashion was defined by different materials that had never been known to be used as clothing. Cropping is a style most commonly used with the tall and slender. Making them look not so freakishly tall but showing off their boy frame. The cropped top has become most commonly used now in high street and mainstream fashion of those that don't want to be categorized as indie etc and just follow to be cool; I call these people the Topshop Clones. If you are american it is much less of a problem, in England especially the Topshop Clones wear bright pink knits with embroided black lips on them, the recent off spring from the Topshop Clones are now the Forever 21 Clones. It is now a common occurrence that a clone would have the same top as another. Of course I shall not slag these shops off completely because the more alternative exclusive stock of Topshop is not so bad.  

Anyway...  back to cropped. I think this trend although exclusive is flattering and when done well can be the most stylized peice in your wardrobe...