Understand your limitations. Yes, each person does have limitations — natural and conditioned. The natural limitations such as IQ are pretty hard to impossible to overcome, but negative conditioning, while not easy to overcome, is well worth identifying and working hard to rise above.
Genius is a natural gift that can’t be attainted through practice. Failure, however, is most often a combination of bad luck or bad habits or a lack of knowlege or positive persistence. In other words being born a genius is nice but not a perquisite for a successful life — always learning and improving is the true way of life no matter one’s base starting point.