SOcialism leads to crony capitalism--those with connections get the good food and the nice cars and the good healthcare and those without connections do not. It is a "connections based" economy. Capitalims is a merit based economy. Both involve luck (luck in who you know with socialism, luck with market timing for capitalisms).
Importantly, socialism inevitably leads to oppression since it suppresses the fundamental individual drive for self preservation, whereas capitalism attempts to leverage that fundamental individual human nature.
Both have inequality, and neither is perfect. The key is where the average line of prosperity is drawn (averaging societal wealth). Capitalism draws the average line higher than socialism does. Both have people fall through the cracks, and are therefore not perfect, but one is "less imperfect" than the other, and that one would be capitalism.
The Soviets learned this lesson. We didn't believe them, apparently, and began our own experiment on the topic with the Great Society. I would rather stop our slow slide into socialism, but I despair that we can stop it.