Cons
HR has very confusing rules regarding OKRs. For some employees, if you fail to meet your OKRs, you can be laid off—they'll cite efficiency as the reason. For others, however, they can continue working as long as they do not receive a bonus or salary increment. It seems to depend on whether HR and your supervisor like you or not. As a result, you have to keep them happy all the time to avoid being laid off.
When you decide to resign, you may have to wait a month to receive your reference letter. Sometimes, you even have to beg the HR manager for it. It's very strange because a reference letter is a worker's right, though.