Ayn Rand saw collectivism in all its forms as an impediment to human rights. "The good of society" cannot be the basis of rights, since society is merely a collection of individuals, and so the only proper rights are individual rights. When we base rights on what is good for society, that begs the question: Who speaks for society? Throughout history, such people who claim to speak for society inevitably turn out to be tyrants. You have a few, even a single person, deciding what is good for the people. Rand thought that people ought to decide for themselves, based upon rational self-interest.