In the case is of Danube, it wasn't so much the negative reviews as the disappearance of a great many positive reviews. After each of my meals at Danube, I posted glowing reviews at TripAdvisor. There were quite a number of excellent reviews, some by people I knew, and Danube managed to reach the Number 1 spot on TripAdvisor's recommended restaurants. Then, overnight, almost all of the good reviews, including my own, disappeared - deleted by TripAdvisor. And Danube went from the top of TripAdvisor's ratings to the very bottom. After numerous attempts to reach someone - ANYONE - at TripAdvisor to get an explanation, I learned that an anonymous source reported to TripAdvisor that these good reviews of Danube were fake, or purchased by Danube in exchange for free meals. A completely false report, probably made by a competitor of Danube, but TripAdvisor just decided to delete all of the good reviews without ever even checking on the report. Danube failed from lack of business, and TripAdvisor completely lost any credibility, as far as I am concerned.