The biggest reasons the U.S. hasn’t adopted the metric system are simply time and money. When the Industrial Revolution began in the country, expensive manufacturing plants became a main source of American jobs and consumer products. Because the Imperial System (IS) of measurements was in place at this time, the machinery used in these factories was developed to size in IS units; all of the workers were trained to deal with IS units; and many products were made to feature IS units. Whenever the discussion of switching unit systems arose in Congress, the passage of a bill favoring the metric system was thwarted by big businesses and American citizens who didn’t want to go through the time-consuming and expensive hassle of changing the country’s entire infrastructure. Many also believed that the United States should keep its particular system, setting it apart from other countries and symbolizing its status as a leader rather than a follower.