Poor Performance of an employee also depends on the attitude of the co-workers too,since when a person joins in a company they get influenced by co-workers and how they tell about their seniors.
To speak frankly, In my Previous organisation,people who used to work hard were not reconginsed but people who acted as if they work hard were recognised,there should be no inequality in treating people.This leads the hard working person also to do poor performance,since he is not recognised, we always cannot say that management people or senior people in the comapny is correct, indeed they should be the role models, when all these aspects lack this naturally leads to poor performance.
I dont know how far the above is correct, but this has played a very vital role in my previous organisation.