BOGOFS

According to research from the Advertising Association, buy-one-get-one-free (BOGOF) promotions don't necessarily encourage consumers to buy things they don't want. More than two-thirds of consumers see these promotions as a way of helping out with their finances and only one in five say it encourages them to buy things unnecessarily. However the Chartered Institute of Marketing has pointed out that it is difficult for a brand which has price promoted heavily to return to its former premium positioning.
Marketing Week, 1 October 2009, p7