> I think you are misreading the person you're replying to. [...] They're saying "don't quit just because you aren't great on day 1."

That's not what they're saying. They literally wrote, "you'll be bad at anything new". That's what I disagreed with. There are people who are great at something new (for them), and catch up with (and surpass) old-timers incredibly quickly. And their learning experience -- not that it doesn't take effort -- is generally enjoyable, exactly because they succeed from very early on. I've witnessed this with at least two colleagues. Entered completely new fields (one of them repeatedly), and in a few weeks, surpassed old-timers in those fields. These are the guys who tend to be promoted to senior principal or distinguished software engineers.

> First time playing basketball even if you've played soccer a ton and have good general athletic ability? Don't expect to hold your own if joining a game being played by people who play every week.

Do expect to mostly catch up with them in 1-2 months! (In my high school class, the soccer team was effectively identical to the basketball team.)

> and done in 1/10th the time

I agree with this; yes. But my point is that, for some people, approaching such a short completion time, with comparable results, is a relatively fast, and enjoyable, process. They don't plateau as early, and don't struggle from the beginning.

> If you believe "guess I just don't have innate ability here" you'll give up and never get good.

Correct, but it doesn't imply that "giving your all" does make you good (at an absolute scale). You will no doubt improve relative to your earlier self, but those advances may not qualify as "competitive", more globally speaking. Giving up (after serious work) may be objectively valid. For some people, persevering is the challenge (= lack of willpower, persistence); for others, accepting failure / mediocrity, and -- possibly -- finding something better, is the challenge.