You have good points. I would like to supply some examples to illustrate mine. Suppose an employee is dissatisfied. In the presence of a cliff in the near futu

You have good points. I would like to supply some examples to illustrate mine. Suppose an employee is dissatisfied. In the presence of a cliff in the near future he may be hesitant to stir the pot and instead decide to wait for it before bringing this up. Meanwhile not being heard he will accumulate resentment. On the other hand, suppose an employer is dissatisfied with an employee. With a looming cliff the employer may decide not to risk it a fire the employee beforehand. Absent the time pressure of a cliff they may be able to take time and talk through the problems. None of that would be a problem if performance discussions were happening throughout the entire year. But the cliff serves to hide the problems until they explode the day before or the day after the vesting day.