Most salespeople learn to live by the phrase "The customer is always right." But a recent study suggests stores may sell more if salespeople adopt the attitude "I am never wrong."

A luxury shopping-related research study, aptly titled Should the Devil Sell Prada?¸ suggests that consumers are more likely to make purchases from upscale retailers if salespeople are rude or snobby.

In the study, participants rated their feelings about brands and their desire to own them following imagined and real interactions with sales representatives. Some salespeople were polite, while others were rude. Participants who expressed a desire to be associated with high-end brands reported an increased desire for the luxury products after interactions with the rude salespeople.

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“It appears that snobbiness might actually be a qualification worth considering for luxury brands like Louis Vuitton or Gucci,” University of British Columbia's Saunders School of Business professor Darren Dahl said in a statement. “Our research indicates they can end up having a similar effect to an ‘in-group’ in high school that others aspire to join.”

However, the study doesn't mean all salespeople should stop smiling at customers. The effect only applied if the salesperson appeared to be an authentic representation of the brand. In other words, bargain shoppers at Wal-Mart or Target are not likely to be convinced to buy a dress by a rude salesperson. However, at Prada, it may be in salespeople's best interest to look down their noses at customers. 

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