A recent article was published in a UK paper about an Amazon Distribution Center. One of the paragraphs in the article highlighted the importance of multiple metric labor standards:
Employees can be seen walking up and down conveyor belts rattling boxes before cherry picking ones full of smaller items to meet their quota. A colleague said: “My girlfriend says even the old ladies on night shifts have been fighting over the boxes.” The Mirror – November 26, 2017
This quote reflects the distortions that can be caused by single metric labor standards. The article states that the labor standard for packing was based on “items per hour”. Therefore a box that contained several items would make it easier to achieve the goal. This led to employees walking up and down the line, shaking boxes and then cherry picking those that contained many items.
To avoid this problem, labor standards should be based on multiple metrics if necessary. In this case, allocating time for each order, plus additional time for each individual item in the order would eliminate the problem. Each box would have a fair labor standard associated with it based on the number of items it contained. This would eliminate the inefficiency of employees walking up and down the line looking for easy orders, and it would also eliminate the conflict that can be caused within a work team when employees are incentivized to cherry pick certain orders.