Did you know that over 25% of the bones in your body reside in your feet? The concept of why we all need custom orthotics like these is simple... If our feet or not aligned, then everything above (joints, muscles, structure, center of gravity, tendons, bones, nerves, bones, proprioception) compensates to some degree. Try to picture building a house. If I start with a foundation that is not level and sound, everything else above will have to compensate for that discrepancy. Why have extra wear and tear on our bodies if we can do something about it?