"Meanwhile, Glassdoor has no incentive to keep it all clean by making participants accountable" Is this true? Do the users not value quality? Surely they'd be

"Meanwhile, Glassdoor has no incentive to keep it all clean by making participants accountable" Is this true? Do the users not value quality? Surely they'd be more likely to use and continue to use the site (and by extension, increasing Glassdoor's revenue) if they perceive it to contain useful, objective reviews?