Seeing failure as a precondition to improvement seems more valuable to me, than the inverse of:
I’m not as skilled as I think I am, therefore I will not try XYZ thing.
This then is a feedback loop of either slower or “negative” improvement overtime.
This goes without saying that for some cases over confidence can be detrimental:
I was confident I was a good snow boarder despite going only a few times years back, and decided to start back up going down a blue trail, only to end up needing knee surgery.
Or you try it knowing there is a learning curve and that you will never be great. People can still participate and enjoy things knowing they are only mediocre at that.
Not always. They can also be blinded by the current state of things instead of thinking of new solutions or challenging the status quo. People can be over confident in their code and refuse to write tests or their assumptions based on old knowledge and go down the wrong path...
But when one side of those balancing acts gets into focus too much it can become an arms race, a success metric that in a way becomes self-fulfilling more than it deserves. If we look closely, and freed somehow from our baseline expectations (to an American, confidence arms race will just feel normal), we can probably detect similar patterns in just about any community.
Funny personal anecdote:
Hiring manager: "Why should we hire you?"
Me: "I'm not sure you should. It depends on the quality of your other applicants."
I'm still tickled by how much that caught them off guard. Radical honesty is one of my mild-Asperger superpowers :)
Someone: Wow thats a good idea!
Me: Uhh I think it might be a terrible idea.
I try a lot more things than I would if I believed I weren’t capable, which means I learn more than I otherwise would (including learning from failure), and all of this extra knowledge makes me more capable than I would be if I settled for a pessimistic view of my capability.
Whatever your attitude toward Americans, I think you would be doing yourself a disservice by settling for a small view of your potential.