Knowing what you want from life is something that can help you focus and channelize all your mental and physical energies to things that really matter to you in life.
This is true in every aspect of life like relationships or career.
From the career viewpoint, if you have well written short and long term objectives, then you can do a proper career planning for how to proceed to achieve those objectives.
Stated simply, developing a habit of writing your career goal statements can have positive results in attainment of those goals.