In most ballparks, the locations of the on-deck circles seem to be dangerously close to the batters boxes. However, rarely does anyone see balls hit directly at batters waiting in the on deck circle. You see plenty of line drives directly into dugouts, which is actually further than the on-deck circle.
Is this planned? Did someone study the angles that foul ball line drives are hit, and determine where to place the on-deck circle? Or was the optimal location “learned” through experience?