The More Is Less Effect: How Adding Positive Arguments Can Undermine Attitude Toward an Object

Kurt Carlson, Georgetown University, USA
Suzanne Shu, University of California at Los Angeles, USA
This article posits and tests whether four positive arguments are less persuasive than three due to a sense that the source is trying too hard. Four studies demonstrate this more is less effect in domains as varied as cereals, restaurants, and politicians. The effect is attenuated when claims are verified by a credible third party, when consumers are under cognitive load, and when a single negative attribute is added to the list of positive claims. Given its generality, we believe the more is less effect has important implications for nearly every aspect of marketing related to persuasion.
[ to cite ]:
Kurt Carlson and Suzanne Shu (2010) ,"The More Is Less Effect: How Adding Positive Arguments Can Undermine Attitude Toward an Object", in NA - Advances in Consumer Research Volume 37, eds. Margaret C. Campbell, Jeff Inman, and Rik Pieters, Duluth, MN : Association for Consumer Research, Pages: 491-491 .