Consumers Prefer Products That Work Using Directionally Consistent Causal Chains.

The article investigates how the directional consistency of causal chains—sequences of increasing or decreasing steps describing how a product works—influences consumer judgments of product efficacy and choice. Across ten experiments involving various product categories, consumers consistently preferred products whose mechanistic explanations featured directionally consistent causal chains (all steps increasing or all decreasing) over those with mixed directionalities, attributing higher efficacy to the former due to greater processing fluency (ease of understanding). This fluency mediated the relationship between directional consistency and purchase likelihood, while increasing the length of causal chains reduced fluency and attenuated these effects. Additionally, consumers' prior knowledge could moderate this preference, weakening the influence of directional consistency when familiar but directionally inconsistent mechanisms were involved. The findings offer theoretical insights into consumer causal reasoning and practical guidance for marketers on framing product descriptions to enhance perceived efficacy.