I know I'm slowly getting there because I can observe the direct correlation between how I've shifted my thought patterns, and how the situation around me has shifted. One could posit coincidence as an explanation, and that may be true, but the areas of my life where I don't apply this "growth" mindset are the ones that haven't grown. Try it for yourself and see if it does anything for you.
Another example, with contrast between areas where I'm applying the mindset and those where I'm not: learning. In my work, I've blown away the excuse that "I don't have the time to learn" - I was lucky that the circumstances forced me to. As a result, I am now basically an expert on tax credits and grants, and adding more similar fields as time passes, without any hesitation.
Conversely, I've had a "I just need to get things done" attitude to programming and fiction writing over the last few years, and those have budged little if at all. I know that's the wrong mindset, but it takes time to get over it.
Is this the kind of example you were looking for?
This is contrasted with the self-sacrifice mindset, where a person makes decisions that will hurt them and benefit other people or no one.
Also, worth pointing out that I never intended to imply that this "lifelong habit" can't be acquired. I'm slowly getting there, and I started from a strong self-sacrificing mindset.