Of course not.
Think about how the platform works. How would you penalise someone who is ultimately not a resident of the platform?
You can't judge what you can't find - clients are anonymous strangers. Considering that many of them come here for a one time job, there is no effective way to make them behave honorably without also driving them away at the start with complicated rules.
It's a tradeof the platform has to make to keep at least some of us working. And yes, it is a flawed mechanism.
We have statistic about our performance, why the can have the same?
We are penalized for closing contracts or for a client not recomending us, but we dont have the proper tools to select an adecuate client.
Similarly to freelancer parformance reviews, Upwork team also periodically reviews clients' performance. Hire rate is an important factor that is considered during such review. In some cases if the performance does not improve, a client's account can be closed.