There is a saying, "In order to get fine wine, the grape has to get squashed." Adversity is one of the best catalysts for change. It is in man's nature to resent or resist, but it is through this willfulness that great things can occur.
Most times, we underestimate our capacity and capability, but adversity shows us just where we are and what we can do. It is only when we are pushed up against a wall with no choice that our true character shines through. At that moment, our eyes become opened to our true strength.
Sometimes in life we just have to be shown it in order to realize it. We are all capable of doing and being so much more.