Final answer:
Direct labor charges saved due to the increased speed of a new machine are an incremental benefit. They are relevant for analyzing the investment's cost-benefit, aligning with historical evidence that technological improvements can bring substantial productivity gains.
Step-by-step explanation:
The direct labor charges that will no longer be necessary because of the increased speed of the new machine should be considered as an incremental benefit. When replacing outmoded equipment with a new machine that operates more efficiently, the savings on direct labor costs are relevant to the cost-benefit analysis of the investment.
These savings are a type of opportunity benefit that comes from investing in improved technology, which can often be scaled across different areas of the business with very low marginal cost. As seen in historical examples, such as the internet or the steam engine, technological advancements can yield significant productivity gains without running into diminishing returns.