The erosion of repeat-purchase loyalty

A large-scale longitudinal analysis is used to study the repeat-purchase rates of brand buyers in stationary markets. The data cover the leading brands in a number of frequently purchased grocery categories in three countries. We find that, in the medium term, there is a systematic but limited loss of repeat-purchase loyalty; across nine markets, erosion (the proportionate fall in repeat-purchase loyalty) averages 15 percent in the first year for the brands studied. Erosion does not differ by weight of purchase: similar rates are found for light, medium, and heavy buyer-segments. Brand leaders are found to have a lower erosion than smaller brands.