When most people wake up in the morning and get out of their bed, they do not need to concentrate on standing up. In fact, the last time many of us concentrated on standing up was when we were babies. When we were learning how to walk for the first time. Carefully holding ourselves up for the first time, wobbling about before we fall on our ass, and try to do it again, and again, and again until it becomes second nature. And at hat point, we no longer concentrate on standing again.
That is a problem when we hit. Because we never really focus on standing, we have a tendency to neglect that when we hit. Standing and standing strong is imperative to being a powerful hitter. Feeling the ground securely, no wobbling what so ever, the concentration process of standing. To maintain a specified position or posture. Make sure the ground is our stabilizing force to explode past the baseball with balance and movement that the brain actually thinks we are doing is the difference between good and great.
So next time you get in the box, be a baby and stand for the first time again.