[blahblah3]

Yes, preparation makes a big difference in math olympiad but most of those competing at a high level are already very talented to begin with. The problem is when a parent expects their kid to achieve similar performance when they don't have the raw skills. By attributing no role to inherent ability, blame is always put solely on the child for not trying hard enough. Even within a given family, you'll notice that some kids are better much more talented than their brothers or sisters at a given task, and the difference is not really preparation (especially since these differences can often be seen at a very young age).

[jiaweihli]

You're describing a fixed vs. growth mindset. This applies both to your current perception of people (notably children), and also your perception of yourself when you're a child.

I believe in the growth mindset - to explain your example of sibling dominance, I believe that a child's mindset heavily influences their ability to learn. If it has a positive effect, the preparation they do is both more effective and more bountiful (this is usually classified as stubbornness / determination). But preparation _is_ necessary to perform a task at a high level. When you hear of 'prodigies', they often started whatever it was - math, music, sports, programming - at a very early age, and reaped the interest.

[blahblah3]

Why not both? Both preparation and inherent ability are important. I find it implausible that everything can be explained by "mindset." Perfect pitch is a good example, it's a useful ability and cannot really be developed through training. Other factors are more subtle but are also fixed.