Well, but they aren't doing so right now, because labour has costs. If your existing labour suddenly gets more productive, there's still a trade-off between co

Well, but they aren't doing so right now, because labour has costs. If your existing labour suddenly gets more productive, there's still a trade-off between cost and benefit to be made. And it would be a great coincidence if the optimal trade-off were exactly at the same headcount as the old trade-off under the old productivity figures. It's more likely that the optimal trade-off for the business under the new conditions is at some other headcount.