Natural talent and gift is just excessive exposure very early on.
Takes someone who is called a "math genius" in high school for example, everyone will just assume he/she is naturally talented at maths, no-one will think to ask he/she how much maths they did in primary school. In actuality they did maybe three times, even more, the amount of maths that everyone else did. And at primary school level this isn't very much, maybe 20-30 minutes a day? But after years it adds up - the time spent accumulates to a total that cannot be reached with a single year (Y12) of effort.
It's too limited to just look at work done in Y12. Even if this supposed genius is lazy throughout his/her high-schooling years, his/her years of work during primary school still puts him ahead of the majority half a decade later in Y11/12.