I spent more than 30 years of my life in high volume production/maintenance both a grunt and a supervisor. In both roles I counted on such metrics to evaluate first my performance and then others'. Metrics can only be "gamed" by those in charge being as they are the ones who set the parameters of the game. As a grunt (a term I use proudly), neither I nor my fellow trench-mates, had the liberty to change any part of the metric du jour. My only option was to either find the most efficient way of doing my particular task or not. While I chose the former path, some coworkers chose "not". We didn't have the option to change either the particular item to be produced nor how many were required to meet quota. We did have direct influence over quality. As a supervisor, I still didn't have the luxury of changing volume required and my influence over quality was converted to using the available employees in the most efficient manner possible. My point is that when the discussion concerning the use of metrics in production is limited to "other than Russian production from Hell" the whole notion of gaming metrics is relegated to upper management and rarely has any bearing on the floor-level employee. We were pretty much masters of our own employment destinies.