A tough question for anyone to answer as definitions can come from just about any angle. There are some who measure true success simply by the amount of money one makes, and I suppose that is one measure of success. Others would consider the level of higher education one achieves as "making it" (PHD, MBA, etc.), while a significant population sees the position one holds in their profession (CEO, CFO, etc.) as the defining factor.
From another perspective, some view a person's level of accomplishment (awards, honors, commendations, championships, etc.) as the measure above all others. However, there are still more viewpoints out there, as others (a good number I might add) might use a combination of criteria, likely including many of the things mentioned above, as to what it means to truly be successful.
One last perspective on true success is depicted in the following interpretation.
Thoughts are welcome!!!
The willingness, perseverance, and commitment to go through a process that allows one to achieve personal, family, and/or group goals; the kind of goals that many view as impossible to accomplish.
And to do so with solid character and integrity, the kind of character and integrity that beseeches one to do the right thing just because it is the right thing to do. This is regardless of the outside pressure to do otherwise.
Finally, the readiness and resolution to reach out to others in order to teach them how to do the same.
It is this kind of success, true success, which brings with it an internal sense of gratification and happiness that can be difficult to quantify.
It most certainly cannot be measured by the size of one's bank account, the money one makes, materialistic things one owns, nor prestige or power one believes they hold.
In fact, it is those who try to measure true success in this manner who diminish the real essence of what it is all about, and in so doing never really grasp its completeness.