It's not measurable.
"Success" can only truly occur internally, because it is based on emotion. At the most basic level, success if your relationship with yourself. Most people are living a lie. They purposefully ignore and distract themselves from what they deep down want for themselves.
Many people want something more for themselves. They have dreams and ambitions. Yet, few of these people ever get what they intended.
Being ambitious isn't enough. Far more important than ambition is commitment.
When you're committed to something, you will be and do what is required for the attainment of that thing. You'll stop wondering and start building. You'll stop being distracted and start learning. You'll start connecting. You'll start failing. You'll get what you want, rather than have a long list of "ambitions." You'll have actual accomplishments that reflect your inner goals and values. Your external environment will reflect your deepest internal views and aims.
If you're committed to a marriage, you'll change in whatever ways are necessary for your marriage to thrive. You'll become what is required to make it work. If you're committed to your craft, you'll change and become what is required to do work at the level of your desire. You won't point to your limitations with a victim mentality. You'll change your limitations so they stop stopping you.
Only those who are truly committed will become a new and different person in order to live their commitment.
If you're not willing to change, then you aren't committed to anything beyond what you currently have. If you don't believe you can change, then you can't commit to anything beyond what life randomly throws at you.
The Myth Of The "Unchanging" Self
"Become a millionaire not for the million dollars, but for what it will make of you to achieve it." -- Jim Rohn
Your life is a reflection of you. If you want to change your life, you have to change yourself. If you want to change the world, you have to be that change.
If you want to become a millionaire, you need to become the kind of person that can do that. If you want healthy relationships, you need to become the kind of person that has healthy relationships.
Interestingly, in our Western Culture, we falsely emphasize fixed traits and "personality" types. We believe very strongly in an unalterable "nature" which is uninfluenced and untouched by the environments in which we reside.
We believe something about us is self-contained, and exists outside of space and time. This is individualism at it's finest, and it leads us to believe in some theoretical and "true" version of ourselves, which cannot and does not change.
The truth is that you are always changing. Your brain and even biology are highly malleable. Your worldview is continually integrating new information. When you change a part of any system, you change the whole. Thus, overtime, as you have new experiences, surround yourself with new people, and learn new things, you emerge as a new person. Yet, these changes occur gradually and in real-time, and thus are almost impossible for you to notice.
Yet, as you learn new things overtime, your brain literally creates new connections and is reshaped. The brain you will have in a year from now will literally be a different brain than the one you have now. Especially if you consciously reshape how you see and live in the world.
Consequently, when you become fully committed to something, you throw the individualistic myths away. You are part of a dynamic system that is constantly changing.
When you're committed, you stop justifying mediocrity in the name of authenticity.
You stop lying to yourself about what you want and what you believe in.
You create an environment that facilitates your commitment, because you know that as a person, you take on the form of your environment. The only agency you truly have is to choose the influences that shape you, both internally and externally.
If you're not committed, you rely on willpower. You remain indecisive. You leave things up to chance.
You leave yourself outs. You never fully decide.
When you're not committed, you live in a continual state of self-hatred and internal-conflict. Over and over and over, you watch yourself consciously behave in ways that oppose your highest ambitions.
Only Those Who Are Committed Succeed
Being ambitious isn't honorable. Wanting more for your life is a common desire.
But being completely committed to something is not common. It's rare. It's rare because commitment requires, in the words of T.S. Eliot, "nothing short of everything."
The hardest thing you will give up is the false idea of what you think you are. You have no clue what you are. More importantly, there is no "you" that is fixed and permanent, only the individualistic idea you have of yourself.
This "authentic" self is your worst enemy. It's the excuse you have for not evolving. It's your justification for not committing to something bigger and better. It's the chain around your neck, stopping you from putting yourself into situations that will demand you become a better version of you.
As researcher and professor, Adam Grant, has said, "But if authenticity is the value you prize most in life, there's a danger that you'll stunt your own development... Be true to yourself, but not so much that your true self never evolves."
If you're truly committed to something, you will shape the circumstances which support your commitment. You'll let go of even things you once loved, which contradict the ambitions you truly want.
Unlike the many people who want more for themselves but never truly get it, you'll evolve. You'll be and do more than you ever thought possible, because your current self and worldview is extremely limited. And your views, as well as yourself, will change.
Will you succeed?
Will you be honest enough with yourself to evolve?
Or will you continue living a lie? Will you continue pointing to some imaginary version of yourself you must be "authentic" to?