Knowing your purpose [the reason for your existence] is the key to unlocking your full potential. Without understanding WHY you exist, you will struggle to know WHAT to do with your life.
Think of it this way, a spoon and a knife are both cutlery utensils, but each has its unique purpose. If the spoon tries to go through life, thinking it is a knife that can cut/ slice/ chop through things, then it is guaranteed to suffer from chronic failure and disappointment. It will despise everything that defines it; the oval/round bowl shape and its blunt edges. Yet the day the spoon discovers that its purpose is to scoop, stir and put food in the mouth, only then will it awaken to its full potential.
Do not despise what you have or who you are, instead use that to figure out your purpose. When you do, pursue it until you realise your full potential!