Line balance is the whole game
A line runs at the speed of its slowest module, and every machine faster than that is only producing a queue. Balancing means matching machine rates to a common takt and putting buffering where the variation is, so a short stop upstream does not empty the downstream machines. Surge capacity is what absorbs the ordinary chaos of a real shift. Get this wrong and you have bought throughput on paper that the line never delivers on the floor.
