Why did Olmec farmers more their farms from time to time

Olmec farmers moved their farms from time to time in order to practice slash-and-burn agriculture. This method involved clearing and burning patches of land for cultivation, and then moving on to new areas once the soil had been depleted of nutrients. By rotating their farmlands, the Olmec were able to maintain soil fertility and prevent the land from becoming infertile due to continuous cultivation. This practice allowed them to sustain their agricultural productivity over time.