There is only one place where socialism has ever worked; that is, in the family. Not all families work this way though probably they worked more so in the past than in the present. The families of my grandparent did operate this way; it is of note that both existed in the times of the Great Depression and before.
What are the aspects that allow it to work? It starts with “blood is thinker than water.” It moves on to “all for one, and one for all”; that is, a shared destine. Note that this concept requires buy in, and is somewhat fragile. In the center a successful families is strong leadership. Not only is it strong, it has the best interests of the unit in mind. Furthermore, it will work to attempt to arbitrate disputes fairly and to distribute work and rewards in an equitable manner. All of this is possible because the situation(s) are known and understood to the leadership. And in the end, the leadership often sacrifices greatly for the good of the family unit.
How well does this schema scale upwards in size? Poorly. Leadership, despite their protestations, always take liberties. Think in terms of the pigs of Animal Farm. Since the only way to effectively implement this on a larger scale is through undemocratic force (EU, I am looking at you), taking such liberties naturally happen. Furthermore, these leaders do not really have the best interests of their subjects in mind. They convince themselves that they do, but in reality, they like doing well by doing (supposedly) good. And in the end, the leadership almost never sacrifice at all for the good of the people.
Though perhaps we should cut these leaders some slack, There is no way that they can ever really understand the true situation with their subjects. So even if they wanted to, they could never arbitrate as fairly and family leadership could.