"Work being done" refers to the output, not the way in which that output is produced. For example, let's say that the task is to add up a list of 10,000 number

"Work being done" refers to the output, not the way in which that output is produced. For example, let's say that the task is to add up a list of 10,000 numbers. It might take a human a while to accomplish this accurately. A computer won't take much time at all. The computer is accomplishing the same work as the human in a much shorter amount of time. The computer could handle a vast number of such tasks per day for a lower price than any human, with better accuracy. Similarly, imagine hauling cargo across the country. A human could put the packages on their back and walk, or alternatively a human and freight train team could haul them by rail. The human and freight train team accomplishes vastly more work than the human alone, and is able to haul much larger and heavier packages at a much faster speed.