These star-studded collections offer much appeal to today's celebrity- and designer-obsessed consumer who is intrigued with those in the spotlight. The designer/celebrity partnerships, in turn, boost the retailer's image by generating a lot of publicity. In many cases word-of-mouth and celebrity endorsements have been key to building brands.

According to web-based World Wide Words, the term began as a British expression, but is now widely known in the U.S. and elsewhere. It comes from the manufacturing industry, in which off has long been used to mark a number of items to be produced of one kind: 20-off, 500-off. This expression seems to have its origins in foundry work, or a similar trade, in which items were cast off a mold or from a pattern.