"Computers will never match the human eye for detail," was Marcus' answer. It probably depended much more on the subject, but Marcus suspected that since every student had different ways of learning, humans would always be the ones to grade papers, unless the test were done on those little strips you fill out the bubbles on. Even then, there was plenty of room for error.
As the stranger took the last paper, Marcus became curious. "Are you a teacher?" he asked. The man seemed almost nervous to be in contact with another human. That he might be a teacher was surprising.