One Product’s Blessing Is Another Product’s Curse - Spillover Effects Between Certified and non-Certified Products of the Same Brand

On consumer goods markets we see an increasing use of quality labels. Often not the whole product range is certified but only single products of one brand. Following Consistency Theory we expect this labelling practice to have negative effects on consumer’s perception of non-certified products. We deduce from spillover and quality label literature that brand strength and fit might influence the effectiveness of such practices. To test our assumptions, we conducted two online experiments. We find out that products of well-known brands suffer from certification with a quality label of low fit – even if the majority of products is certified.