Does anybody really believe that racial diversity is a good thing?

Just one example I know for fact..A factory I worked at, we got paid extra for going above our quota for our shift, came to around 20% more pay a week, anyway they were forced to hire some blacks, they went through the same training as everybody else. Once the blacks got into my area that was the last bonus I ever saw on my paycheck for exceeding the minimum "quota"....But a least we were diverse, that is the main point, we were told anyway. This is not a "rant" but should be. Any Ideas on this? And remember I said same training, same everything, so don't pull that "card".