A study by an organization called GRAIN concludes that, although small farmers produce more than half the world’s food, they own only a quarter of the world’s land, and that their share is shrinking.
I think the same principle is at work here, to a lesser extent, as was the case in the USSR and China under Stalin and Mao, when forced collective farming resulted in starvation.
On small farms, owners are the same as managers, and, even if they have hired hands, they are not separate from the workers. Naturally they will work harder, pay closer attention and exercise more independent judgment than if they were employees of a big corporation or a government.
Why, then, are large farming operations crowding out the small independent farmers? My guess is that it is because they have economies of scale that lower operating costs per acre, more bargaining power in dealing with lenders, suppliers and food buyers, and, last but far from least, more influence with governments.