Reassessing product line breadth effectiveness: The role of heterogeneity, moderation, and cumulative effects

Evidence regarding the impact of product line breadth (PLB) on brand performance remains fragmented; the current research proposes an influential effect of product equity in determining PLB success. To test these predictions, Study 1 first identifies heterogeneous effects of PLB on brand performance according to the levels of product equity. Specifically, PLB hinders (improves) the performance of low (high) product equity brands. Then Study 2 identifies two drivers of PLB effectiveness, product attribute differences and competitive intensity, that have contrasting influences for brands with high versus low product equity. These influences exert long-term, cumulative effects (i.e., over 104 weeks). To ensure the generalizability and applicability of the findings, this research effort spans a vast consumer scanner data set, involving 268 brand panels, 14 product categories, and three retailers. Based on this collected evidence, the authors propose a matrix of managerial actions that practitioners can adopt to increase their PLB effectiveness.