If your business has jumped on to the Groupon train, you probably have already seen issues arising with customers. Usually these involve misunderstandings such as the applicability of the offer being based on a special product or service, not a blanket discount. Sometimes it's dissatisfaction due to the inability to properly serve the crush of customers.
Three computer scientists from Boston University and Harvard studied the effect of using Groupon deals on Yelp reviews.
Some key quotes:
"Groupon subscribers give businesses on average a 12 percent lower Yelp score than non-Groupon reviewers"
"Groupon subscribers are actually more moderate reviewers on Yelp than the average consumer"
"reviews from Groupon subscribers are lower on average because such reviews correspond to real, unbiased customers, while the body of reviews on Yelp contain some fraction of reviews from biased or even potentially fake sources"
"All this seems to imply that business owners who are wary of their Yelp ranking should either avoid offering Groupon deals or be sure, ahead of time, that they have the capacity to roll out the red carpet when customers flash coupons."
Read article in its entirety: The Huffington Post