Knowing what I know about biomechanics and anatomy, I would still have to support the idea that the shoulder is extraordinarily designed, but I would make the case that it should come with a detailed instruction manual of how to actually use it properly. Your shoulder is a complex ball-in-socket joint that’s function is intimately tied to the posture and alignment of your ribcage and thoracic spine. ‘Normal’ movement in your shoulder requires the ball to spin in the socket, the shoulder blade to slide over your ribcage and your torso to remain in a relatively stable position; a problem in any or all of these factors will lead to dysfunction and eventually pain in your shoulder.
It is not hard to determine what structure in your shoulder may be damaged and hurting, but it can be harder to understand why you damaged anything in the first place. Sometimes why is easy. You may have tried tackling a two hundred pound Kiwi rugby player determined to run through you and your shoulder lost the battle like mine did, but most of the time ‘why’ is more complex than you would like. Shoulder pain usually involves a combination of factors that over time lead to the insidious onset of pain.