Glassdoor is a web site where workers rate their current or former employers. Like all online review web sites, the ratings have become flooded with fake reviews, in this case, orchestrated by employers.

Employers flood the ranking site with 5-star postings requested from enthusiastic staffers, leading to unusual spikes, a WSJ investigation found. This is a conundrum facing many influential raters, including Amazon.com, Yelp and TripAdvisor, who have had to fend off attempts to game reviews.

Source: How Companies Secretly Boost Their Glassdoor Ratings – WSJ

Online reviews – of all types – have become near useless. TripAdvisor was previously caught censoring negative reviews. Amazon reviews are flooded with fake and paid reviews.