How did Ford's assembly line make cars cheaper?

How did Ford's assembly line make cars cheaper? - 1

It allowed unskilled workers (e.g. Cheap workers) to only do one relatively small task on the assembly line and then pass the car to the next worker for the next task. Previously, making most manufactured goods, such as guns, required highly skilled and experienced workers who could essentially do the entire job, with possibly some help from apprentices.

Allowed the Ford company to make more cars and make them cheaper

Ford not only used the assembly line, he was the first big car maker to use interchangeable parts. Before he started making his cars, the parts used to assemble a car were pretty close to right, but not 100%. Each part could need some 'massaging' to get it to work just right, a bit of filing, maybe a slight bend, but they would not just drop into place.