Synergy or Cannibalization: The Effects of Product Demonstration and Bullet Comments in Livestreaming Shopping

Livestreaming shopping, in which streamers showcase products in real time and viewers interact with peers through bullet comments, has transformed the online shopping experience. Despite its rapid growth, the industry faces persistently high product return rates driven by consumers’ unrealistic expectations, indicating inadequate product diagnosticity. Drawing on signaling theory, this research conceptualizes product demonstrations and bullet comments as two salient signals in the livestreaming shopping context and examines how they individually and interactively influence consumer perceptions of product diagnosticity. Across three randomized experiments, we found that product demonstrations positively affect product diagnosticity. The presence of bullet comments enhances perceived diagnosticity but weakens the positive impact of product demonstrations on diagnosticity. Similarly, the relevance of bullet comments improves diagnosticity while also attenuating the effect of product demonstrations. This study extends signaling theory to the livestreaming shopping domain by introducing a descriptive-demonstrative signaling framework. Moreover, it is the first to theorize bullet comments as signals and to propose a “signal cannibalization” effect arising from multiple, simultaneous signals. The findings offer practical implications for platform managers and streamers on how to strategically integrate product presentations and bullet comments to enhance the effectiveness of livestreaming commerce and the shopping experience of consumers.