Why is George's dream of the farm unrealistic?

George's dream of owning a farm is unrealistic due to several factors, including the harsh economic realities of the Great Depression, which make it difficult for itinerant workers like him to save enough money. Additionally, the dream relies on the hope of stability and control over one’s life, which is often elusive for characters in the novel. The constant struggle against societal and personal challenges further highlights the improbability of achieving such a dream.