It is often found commentaries that describe common good as extremes of anarchy, as expressions that on one end present a justification for system interference and on the other as an idea of omnipotence over the people who is typically labeled as mediocre and incapable of deciding on their own about their matters and circumstances.
However, common good is divine a mandate we all have as individuals; to aim for and to work towards. It is what defines the relationship between science and reason, because a science where its object is to benefit only the self or to enhance the egos of the recipients is what defies reason and so it segregates itself from faith which is what make us creatures of God with dignity, identity and individuality because care exists for our neighbor and peer.
Common good cannot be taking or confiscating from some to give to others or to pretend that by robbing from the ones that have to presumably give to the have not, the issue is fairly addressed. On the contrary, when vital resources are denied to an individual or family even though the idea or good intention behind it would be of servicing common good, the effect is contrary because common means universal inclusion and the sole act of taking away from one implies a targeted action that goes contrary to the precise premise that defines common good.
Communism or any other denomination for collectivism, including Nazism, are not endeavors for common good but rather and in exclusivity to benefit the few at the expense of the many, to satisfy the egos of the elites that invariably behind any one of these charades.
How ironic it is that the ones that precisely tend to follow common good surrendering their freedoms and dignity to the system, are the ones that reflect the mediocrity that defines how wrong their stance is.
Common good must rise from the heart of the individual and the family as an expression of love or charity, as an effort towards making the goodness available to all, as for oneself, and after loving God over above everything and anything.