Why didn't economic prosperity help insure political stability in Cuba?

Cuba

AMERICAN INGENUITY INDUSTRIALIZED the sugar industry in Cuba. Larger mills were built. Railroads were added to carry the cane to centrales that now dominated Cuba's sugar production. Corporations, principal among them American Refining Company, Hershey Chocolate Company, Hires Root Beer Company, and Loft Candy Company, acquired the largest plantations. Production rose. Profits rose. The latifundia (large plantation system) thrived on cheap labor and American capital.

Latifundia is derived from latifundium (latin for great estate). Such great farms were found in ancient Egypt and Rome (as in Cicero's Latifundium pictured here - click to enlarge)

Unfortunately, the latifundia proved too successful. The island began producing more sugar than even the United States could consume. They turned to other markets but found them closed by World War I. Thus, the price of sugar plummeted and granitos or little farmers were forced to sell their cane to the centrales at lower and lower prices until they had no choice but to sell their farms to the larger plantations. The colonos or workers became vassals of the centrales. 

Until the 1920s, Cuba's economic policy had been guided by the Americans who insisted that the island could achieve prosperity and political stability through increased production of sugar. The capital investment in Cuban sugar and other properties which had increased from $50 million in 1898 to $1.25 billion by the mid-1920s, wasn't producing the expected return. Then came the Fordney-McCumber tariff of 1922 which levied extra duties on Cuban sugar imported into the United States to offset the damage done to the sugar beet industry in Colorado and the competing sugar cane industry in Hawaii.

Thomas Chadbourne, a lawyer from New York, was retained to represent Havana at a convention in Brussels where ministers from the sugar producing nations were meeting. Together with Java, Czechoslovakia, Germany, Poland, Belgium, and Hungary, they agreed to limit production and increase sugar exports only as prices rose. The plan produced only marginal results.

Ultimately, the prosperity that was supposed to insure political stability in Cuba never materialized. Thus, political stability never materialized. At no time in the decades that followed, from the end of the Spanish-American War until Castro's rise to power, did any Cuban government ever sit easily in Havana. Stability was only achieved so long as the threat of American intervention prevailed, and the island's government remained committed to maintaining the status quo for American businessmen on the island.