The elements in life that require the most balancing can be divided into two categories: internal and external. Most of the time, people focus on one more than the other. Hence unbalanced.
You may find that you focus on external things,like work, relationships, and activities, and that you pay little attention to what is going on inside your heart and mind.
On the other hand, you may find that you spend so much time being self reflective that you sometimes miss out on the experience of living.
Other people may be fairly balanced between the two but might want to balance out some specific elements within each category. Is it not worth our time reflecting where we put most of our energy and try to change where we put our energies.