Setting time aside to define personal success is not a priority for everyone. If you are in a job you enjoy and have a career direction you are happy with, there is little need to have this conversation urgently. However, if your job and career are offering little by way of enjoyment or satisfaction then this question begins to demand some of your time.
If change is something your career will need to face in the future a simple equation is worth considering. The more time you spend on this question now, the more your answers will support you when they are needed most.