<human>:  Why did Henry Ford invent the assembly line?
<bot>: Henry Ford invented the assembly line because he wanted to make cars more affordable. He did this by breaking down the process of making a car into a series of simple steps that could be performed by many workers at once. Ford wanted to reduce the amount of time it took to build a car from hours to minutes. This was a big deal because it meant that more people could afford to buy a car.