I read with some amusement that a "company" has ambitions to fly a person to Mars by 2024, or maybe 2026. The best part of this is that one of the founders said, "You have to work hard, but you do not have to be very smart." In a less get-blown-up-in-a-cloud-of-toxic-chemicals social media post, I saw a "viral" post of some parent who told her 7th grade daughter that got cut from the volleyball team to "suck it up" and "work harder" if you want it bad enough.
These myths, that if you "work hard enough," or "pull yourself up by your bootstraps," or other similar flavors, are utter bullshit.
If you want to approach this purely from an observable angle, then look at anyone working their ass off doing physical labor, and tell me if after years of doing it that they're succeeding at making their lives better by working hard. You can't work much harder if you're digging in a mine, loading things into trucks or running around an Amazon warehouse while you take a minute to pee in a bottle. In more practical terms, with regard to the above examples, putting things in space is hard, and some kids just don't have any athletic ability. Working hard does not change the calculus.
This is one of the worst myths that Americans adhere to. I'm not at all suggesting that dedication and commitment to something isn't rewarding, but to be realistic, we have to acknowledge how much luck has to do with success. Let's start with the birth lottery. If you're born into poverty in some remote part of the world, working hard isn't going to lift you out of poverty, at least, not without a lot of luck. You can apply the same standard domestically, because the income of your parents, your race and where you live have a lot to do with how likely you can rise above it all. Hard work alone does not guarantee success.
The nasty cultural side effect of this is that we tend to write off people who can't achieve in the traditional sense to have personality defects. This is the basis of the opinion of people who believe we're already past racism, and it's just cultural differences (which is, ironically, itself a racist assertion). Some folks working in low-wage jobs get trapped in a cycle of childcare negating income. These goofy rocket people won't get off the ground because hard work isn't enough. (OK, so this one might be a personality defect for different reasons.) The early teenager may never develop volleyball skills despite hard work. Don't even get me started about how this applies to fitness and mental health.
I've worked pretty hard on and off for much of my life, with varying degrees of success. Luck and circumstances had a lot to do with the outcome. So yes, definitely commit and dedicate yourself to things, but stop putting this crap on motivational posters.