At the time that F. W. Taylor emphasized the economic efficiency of workers, labour was the most important input element, the product life cycle was long, manufacturing technologies were stable, product design and specifications rarely changed, and demand was steady. Manufacturers therefore accepted the current manufacturing conditions as given and made efforts to improve productivity. For example, they accepted the fact that production setup, inventory, and product defects were inherent parts of their manufacturing systems and did their best to utilize resources efficiently by using less labour, materials, and energy to yield more outputs (products).