If the true measure of the value of any business leader and manager is performance, what is it for the employee?

performance  and contribution

This is conditional, it must be the performance as well. Their performance depends on employee.

The same.

We are all measured by performance.

Each employee, Managers, supervisors, and staff are having different levels of KPI's to measure their performance.   All KPI's should be set to achieve management's short and long term objectives.