If this was the case, then the individuals who are winners in one of their life's endeavors would not be failures at anything else they do.

I don't think we fully understand what "talent" and "natural gifts" are. I believe it includes how our bodies function at the cellular level in how energy is produced from fuel, differences in brain development, and more. Your will can only enable you to do what your body is ready for.

The hormones that kick in during an fight vs flight stress situation giving incredible strength can also kill people. Our bodies are full of checks and balances systems to ensure our survival.