Melville is trying to point out the consequences of having someone do menial labor that requires little thought, but a lot of accuracy, day in and day out. He is also pointing out that people are individuals, not simply cogs in a copy machine. The constant grind of copying documents begins to wear on Bartleby. At first, he would "prefer not to" check his work and finally he "would prefer not" to live. The kindly lawyer tries to help him out, but really doesn't understand Bartelby's problem. Your question asks, "Where is Melville going with all this?" A better question might be, "Where was society going with this?"