Success first and foremost depends on one’s goals, AKA, on what they’re trying to achieve. Whether someone succeeded is entirely dependent on what they were trying achieve successfully, and whether or not they have indeed done so. You cannot succeed when there are no goals complete successfully, because success isn’t about being rich or being worldwide famous, but on your preferred attempt at accomplishing whatever you are trying to be accomplishing.
There isn’t really anything else beyond the importance of setting oneself one or more goals and attempt to reach them successfully, when it comes to the basic notion of success.
Whatever else that is defined as “success”, it is defined so by the accordance of which society values in an individual orthodoxically.
However, your own goals don’t have to correlate those of society, and even if you endured the test of society’s expectations, and reached the desired state of what they call “success”, it is still nonetheless not a success if reaching said goals are not your own goals, because how can one become successful in completing a goal they don’t want to be accomplished at, AKA, a goal that is non-existent in their own preferences?
You cannot succeed in a goal that is non-existent in your own preferences, because that goal isn’t yours but of others. Some of us just learn to go with the flow and adopt the goals others impose on us, but as long as we don’t really want to succeed in a goal that we don’t want, we technically cannot succeed in it, even if we accomplished it, because the end-goal of success is to achieve a state of long-term satisfaction, and if you don’t have that then you’re technically unsuccessful in your own terms, even if you are the opposite in the eyes of others.
Thus, one can define success in their life by whether they are or aren’t satisfied with their current achievements, based on their individually-preferred goals. If you are a wealthy businessman or woman but you despise your job, you are “successful” only on society’s terms, that prefer to have citizenry that generate a lot of wealth, but again, if it’s not your own goals you cannot be satisfied, and if you are yet to be satisfied then you are technically yet to achieve success.