A synthetic user is an artificially generated research respondent created by AI systems to simulate how a real person might think, feel, or respond to questions, concepts, or stimuli. In the context of AI-moderated research, synthetic users are sometimes used to accelerate feedback cycles by replacing or supplementing real participant recruitment. However, because synthetic users are derived from training data rather than lived experience, their outputs lack the emotional nuance, behavioral authenticity, and contextual honesty that genuine qualitative research requires. Enterprise insights teams increasingly scrutinize synthetic user outputs because stakeholders cannot trace findings back to verifiable human conversations, which undermines the credibility and trustworthiness of the research.