Individuals will, by nature, serve themselves. Human beings are selfish and self serving. This cannot be changed by philosophical argument or force of law. It has always been this way and always will be this way. Socialist philosophies ignore or marginalize this reality.
Many attempts to forge a society that puts the wellbeing of the society above the individual have been attempted throughout history. All of these attempts have failed; some spectacularly. Human nature always triumphs in the end.
Even so, the debate continues. Even in the wake of the worldwide collapse of Communism, the hypothetical workers' paradise. Communism was supposed to create the utopia for the masses, where all equally labored and were equally compensated. Unfortunately, Communist societies could not effectively subdue their most threatening enemy: human nature.
The character Gordon Gekko' in the movie "Wall Street" said "Greed is good". Whether or not greed is good is a matter of personal opinion. Gordon Gekko did, however, recognize the reality of human greed and worked that reality to his advantage. As long as there is greed and selfishness, then the individual will always place him or her self before society as a whole. There will always be greed and selfishness, as there always has been.
In Communist societies, there was the party elite, who had all the extra benefits of being so loyal to the cause. In democratic societies, the elite in politics start their career with a small fortune and end it with a large one. Many politicians will champion the poor. Find one who will donate their personal fortune to charity. It is easy to be charitable with other peoples' money. Individuals in positions of power and influence will make sure Number One is taken care of.
All individuals should strive to be a productive, active, positive contributor to society. To expect individuals to have a greater obligation to society than themselves is unrealistic and foolish. The individual wants what is best for the individual. Being a productive, active, positive contributor to society brings the respect of one's peers. The individual would not serve society at all if he or she did not get recognition for it that would be of some future benefit, even if it is only an ego booster. There are few anonymous philanthropists.
Effective, successful societies recognize the reality, however harsh, of greed and selfishness. Capitalism works because of these realities. Communism and Socialism fail because of the same realities. As Gordon Gekko aptly said: "Greed works".