Explanation: The Greek warlord Pyrrhus of Epirus won several battles against the Roman Republic, then only a regional power in Italy. However, as the Roman Republic could replenish their losses, and he could not, he recognized that such ‘victories’ would ultimately lead to his defeat, and abandoned his campaign against Rome. From this, we get the term ‘Pyrrhic victory’, meaning a victory that costs more than it’s worth. The Roman Republic would use this technique (bashing their head against a brick wall until the brick wall got tired of it) to great success in future wars.

Similarly the Qin Dynasty of China was quite… capable of absorbing massive losses in exchange for objectives. While the Qin were fond of… exaggerating numbers in the retelling, as many ancient polities were, there is some truth to their ability to absorb massive losses. The Qin Dynasty managed to marshal a much greater proportion of its population than the previous Chinese states did, which were largely oriented around small retinues of hereditary nobility. The Qin, on the other hand, had a meritocratic, if brutal, system of hierarchy which allowed men of common birth to both participate and be generously rewarded by the central government. People are much more willing to volunteer (or at least not evade conscription) if they think they’ll be rewarded for it!

I think they call that “population control” in China.