Value of focus is tremendous. But if one has a cluttered mind, it is difficult to achieve focus. Such a person has to undertake a systematic inquiry of own thoughts, feelings, mental baggage, and goals for identifying what to focus. This is hard and not many people even attempt it. Not many are aware of how to do it.
Workouts in http://www.learning-leadership.com/blog/lead-to-regenerate/ can help you eliminate clutter and achieve focus on what what matters most.