In the case of the kids, they may have seen older siblings playing soccer and know that it involves kicking a ball, but they don't know the skills involved or the importance of playing together as a team. As far as jurors go, most of what they think they know about trials comes from movies and television - which may or may not bear any resemblance to what we see at the courthouse on a daily basis.
Now, just like the kids, adults in for jury duty have to learn how to work together as a panel. They have to learn the dynamics of the panel and of the room in general. They have to learn the rules of conduct. They have to adjust to a (completely) different mode of thinking.
Kids have to learn how to kick the ball properly. They have to learn how to dribble, how to pass, how to stop the ball and how to shoot. They have to learn that success is achieved when all of the pieces work together and for a common goal. Most importantly, they have to learn to trust their coach.
And how does a coach earn the trust of his young charges? By talking with them, not at them. By using words the kids can understand. By being understanding. By observing how different kids learn in different ways. By knowing which kids need words of encouragement, a high five or a hug. By being patient and realizing that kids move at different speeds. By communicating with the kids' parents. By understanding that the game should be fun and that the kids should look forward to practice and games. By recognizing the dynamics of the group and the relationships among the players.
At trial our mission must be to earn the trust of the jury panel. If the jury panel doesn't trust you, it won't matter how logical and reasonable your argument is -- they won't accept it. If, on the other hand, the panel trusts the attorney, they may be willing to bend over backwards to help him out. They may be more willing to give your client the benefit of the doubt.
While there's not a direct relation between coaching youth soccer and communicating with a jury, it is a good analogy and a different way of thinking about how best to serve our clients.