It is important for a child to be socialized with others because that can take a big effect on them in the future. For example, if a child dreams of one day becoming a doctor or a nurse, they need to communicate with their patient to know what's wrong. Same thing with managing their emotions, even though at some points life can be tough they'll learn to suck it up and move on. Rather than roll on the floor crying like a baby (which is something most people want to do).
But these are just examples. The example I used can just give you an idea of why it would be important for a child to start socializing and learning to manage their emotions young, so it can piece of cake in the future. Hope this helps. And I hope you understand what I'm trying to say. Take care and have a blessed day/night :D