Some workers are just better than others. In most organizations 20% of the people are producing 80% of the work. It’s called the “Paretto Principle”, or 80/20 Rule. I learned it from John Maxwell, but it is fairly common knowledge in business…since the late 1800s.
For instance, 20% of your sales staff is producing 80% of the results. 20% of your volunteers are performing 80% of your services. And so on…
You have high-achievers in your organization who outperform everyone else. You can’t treat everyone the same because these high performers will resent being grouped in with the lesser productive people and will either leave to find a better paying (and more appreciated) position OR start underachieving.
Either way, you lose if you treat everyone the same way.