My oldest son is 2 and a half years older than my middle son. The oldest is built like me. Skinny and not ever likely to put on much muscle regardless of diet and exercise. My middle son has a much thicker build, and has considerable upper body strength for a 3.5 year old. He can hold onto a bar with one arm and support his body weight for an extended period of time.
My oldest has noticed that his little brother is stronger than him. And I encouraged him to keep trying to hang from the bar to develop hand strength. At dinner I mentioned that he should eat the nutritious food we give him for dinner as that can only help him develop strength. But the unfortunate reality is that his potential for strength is just not the same as his brother's. His brother hardly ever eats what we want him to, and will sneak junk food if we aren't careful. Basically his strength comes about because the mixture of genes skewed more towards those that make someone strong (interestingly enough my older brother is significantly stronger than me so who knows whether I passed a recessive gene or if my wife's genetics did the heavy lifting here).
I believe the right thing to do is focus on strengths in both personal and professional endeavors. Does it make sense to spend time and energy to improve an area that will never be stronger than others who are naturally gifted? Everyone has a ceiling, and the bar for excellence is incredibly high. There are about 5 men who win the majority of all Major professional tennis tournaments. I'd say there are 15 legitimate NFL quarterbacks in the world. Everyone else is an also ran and likely will remain that way.
So what should I do with my sons? I should encourage them to gravitate towards activities where they can be strong. What should I do with my business? I should go all in on our strengths and redirect any other efforts back into the strengths. I think it's the only sane thing to do.