What is the importance of sankalpa (intention) and how to strengthen it? Does the world move on sankalpa?

Sri Sri Ravi Shankar:

The mind is full of sankalpa and vikalpa (imagination, fancy). Each work gets done through sankalpa. Even the act of moving our arm is preceded by the sankalpa in the mind. If twenty sankalpas arise in the mind then nothing gets done. When the mind is peaceful and restful then our sankalpa is powerful. The sankalpa of a weak mind is weak and that of strong mind is strong. We can make our mind strong by sadhana (spiritual practices) and knowledge. Then the sankalpa will also be strong. The wise makes one sankalpa in fifty days whereas the ignorant makes fifty in a day.