The seed train is the starting point for a fermentation process. A typical example: 1 culture cryo-tube is added to a flask containing 500 mL of medium.
After 48 hours of incubation the complete flask is transferred to a lab scale fermenter containing 9500 mL medium (5% inoculum ratio). This means on 200 m3 factory scale you will need 20.000 flasks to inoculate your fermenter in order to obtain a similar amount of generations of growth. As you can imagine this is not practical.
If more generations are needed on planned scale of production, make sure to study the effect of more generations and the inoculum strategy on the process on lab scale or pilot scale. Are productivities maintained? Is the plasmid stable? Do viscosities change?