What is the purpose of making mapo tofu thickened two or three times

To make Mapo Tofu, you always need to thicken the sauce three times. The first thickening is to keep the tofu from getting old, and the second thickening is to add color and taste to the soup

When the soup is about to dry up, the third thickening is to collect the juice

After the three thickenings, the taste of Ma Po Tofu with 14 kinds of seasonings is really different.