Previous research assumes that consumers can detect and discount the manipulation of online product reviews or are oblivious to such practices. We posit that the equilibrium occurs due to the cues of manipulation, consumer suspicion and their expertise. Our analysis of hotel occupancy data shows that the effect of adding positive reviews and deleting negative reviews on sales exhibits an inverted U-curve. Moreover, weak brands suffer more from excessive adding. Our laboratory experiments find that adding affects consumer purchase intention, but it also arouses suspicion, which exerts a negative mediating effect. Deleting is more disguised and difficult to be suspected. Novices are more influenced by manipulations compared with their experienced counterparts. Thus, contrary to the popular belief of “fake it until you make it,” excessive adding leads to consumer distrust and may backfire. Deleting exacerbates information asymmetry and results in adverse selection, thus warrants restraint and regulation.