卸膊 literally means to take the pole off from one’s shoulder and refers to when someone shirks their responsibilities. This makes sense when one thinks about the nature of manual work during much of China’s history. Labourers often carried a pole on one side of their shoulder which would be attached to a bucket of water or some other heavy good. This was a useful system, as heavier items could then be carried by two people by placing each end of the pole on the other’s shoulder. However, this only works if each person is carrying their fair share of the weight and those who didn’t were surely looked down upon. Because of this, 卸膊 not only refers to someone who has relinquished his responsibility, it’s also frequently used to describe someone who has passed the buck onto someone else