Human-AI interaction in E-Commerce: The impact of AI-powered customer service on user experience and decision-making

Artificial intelligence is rapidly transforming e-commerce customer service, yet its long-term impact on user behavior remains under-investigated, particularly in emerging e-commerce markets. This study explores this impact within the Vietnamese e-commerce context, focusing on how AI influences customer satisfaction, continued usage, and purchase intentions. The research integrates the Unified Theory of Acceptance and Use of Technology (UTAUT) and the Expectation-Confirmation Model (ECM) into a comprehensive framework, capturing the full customer journey from pre-adoption expectations, adoption, to post-adoption behaviors. Using survey data from 552 experienced users and analyzing it through partial least squares structural equation modeling (PLS-SEM), the study reveals that while usability and responsiveness influence initial perceptions, they are not the strongest predictors of sustained satisfaction. Instead, satisfaction is primarily driven by AI's ability to deliver tangible value and meet user expectations. This satisfaction, in turn, becomes the key driver of both continued AI usage and online purchasing. The findings challenge the assumption that ease of use is universally paramount, demonstrating that in a value-conscious emerging market like Vietnam, demonstrable usefulness and fulfilled expectations are critical for AI success. The key novelty of this research lies in its integration of UTAUT and ECM into a holistic framework that captures the entire AI-powered customer service lifecycle, from pre-adoption expectations to post-adoption behaviors, within the context of an emerging e-commerce market (Vietnam), where empirical research on AI adoption remains limited. This study contributes to the field of e-commerce marketing by empirically demonstrating that, in value-driven emerging markets, customer satisfaction and subsequent purchase intentions are more strongly influenced by AI's ability to deliver tangible benefits and meet user expectations than by ease of use alone. The practical implication for businesses is clear: to foster customer loyalty and drive purchasing behavior, AI-powered customer service must move beyond efficiency and convenience, focusing instead on delivering meaningful value and actively managing user expectations throughout the customer journey.