You could be a star employee with no mark on your record, but if you are not a "favorite" of the manager you will miss out on career/promotion opportunities year over year. Unethical hiring practices and personal or intimate relationships between a boss and subordinate allows for any kind of poor performance feedback to go unanswered (poor performer can even be promoted by their spouse). I saw an employee refer someone for a job on their own team, get paid a referral fee, interview that person, hire them, negotiate their salary and sign on bonus, and then eventually promote them (multiple times) later on. The fact that one person could do all those things is very unethical and HR did nothing about it.