Why Was The Work So Hard For Tree-Ear?

Tree-ear requests that he be allowed to work nine days to repay Min for the broken box. Min reluctantly agrees. The next morning, Tree-ear arrives at Min's, eager to learn the potter's trade. Therefore, Tree-ear is deeply disappointed when Min sends him into the woods to chop wood for the communal kiln. It is hard work and Tree-ear gets a bad blister on his hand that Crane-man quietly cleans and bandages.