There is no negative reviews, if there is negative reviews by freelancer or people looking for freelancer, that mean they hired incompetent freelancer to do their work.

They do not have a very good vetting process for clients looking to hire freelancers. The site is flooded with scammers and clients who use loopholes to avoid paying for work once it's completed. And the customer service to get any kind of resolution for any issue is terrible. They also cater to the clients. Freelancers aren't allowed to file disputes, only clients are allowed to. I use to be a freelancer with them but left due to numerous issues and the fact that you have to weed through so many illegitimate clients to find any kind of reasonable freelance work.

They Rob people