It is well known that anonymous and pseudo-anonymous feedback forums online, like Yelp and Craigslist, have a negativity problem. In emotionally disconnected and consequence-free environments, users tend towards over-the-top and unhelpful negative feedback, and just plain meanness.
I am starting to believe that apps whose services involve human interaction in the real world, ranging from Uber and Flywheel to Instacart and Postmates, suffer from the opposite problem. Feedback forms on these apps are designed in a way that people have incentives to be too nice, not too mean. This niceness destroys the value of the feedback and makes it hard for these marketplaces to measure the quality of their service.