I say an hour lost at a ...

I say an hour lost at a bottleneck is an hour out of the entire system. I say an hour saved at a non-bottleneck is worthless. Bottlenecks govern both throughput and inventory.
 Eliyahu M. Goldratt

Quotes from the same author

Cost Accounting is enemy number one of productivity.
 Eliyahu M. Goldratt
An hour saved at the non-bottleneck is a mirage.
 Eliyahu M. Goldratt