Why do leaves of deciduous trees change color in the autumn?

During the spring and summer, many tree leaves contain pigments such as Chlorophyll, Carotene, etc. There is such an overwhelming amount of Chlorophyll, which trees use for their food making process, during the spring and summer. However, in the fall because of the shorter daytime hours, the food-making process stop and the Chlorophyll breaks down allowing the other pigments of other colors to be shown.