Many marketers define customer loyalty as repeated purchases (or other relevant kinds of transactions) by a customer with a company. But this is overstated and a poor conception for what drives customer loyalty. You might just be the cheapest provider or your store might just be the closest to their home. As soon as a better option comes around, you are left on the cutting room floor. That is not loyalty.
I heard about an innovative program being used by Pret-a-Manger that fits in remarkably well to the motivational psychology principles that I am using in my forthcoming book on gamification (yes, shameless plug there!).
You are all very familiar, I am sure, with the typical loyalty programs that retail stores use. You make ten purchases, you get a stamp for each purchase, and then after 10 stamps you get a free whatever. Free coffee at Starbucks. Free book at the bookstore. Free flowers at the florist.