The dynamics of how events happen is a big mystery. Only one who is 100% in doing can recognise the happening. The healthiest way to apply this knowledge is to see the whole past as happening and the present as doing. If you see the past as doing, then ego and regret come along. And when you see the present as happening, laziness and unawareness set in. Let the happening be for the past and the doing for the present. And the future is a mix of both.
The wise will see the doing in happening and the happening in doing simultaneously. One who does a lot of work will never say he did a lot. If someone says he did a lot of work, it that means he can do more. He has not done enough. Work does not tire you as much as the "doership" does.
All actions happen through consciousness. The world moves because of consciousness. Consciousness expresses the three shaktis as — gyan shakti, ichcha shakti and kriya shakti. Knowledge, action and desire. If these shaktis are aligned, life becomes very smooth. If not, life is in doldrums.
Ichcha shakti is desire, gyana shakti is the power of knowledge and kriya shakti is the power to act. Some people have lots of kriya shakti, but lack gyana shakti. They have the power to act, but there is no knowledge of what to do. When this happens, people become restless. There are people who are not so active - lack of kriya shakti. Such people will simply sit quiet but their minds will go on working. Then there are people who lack ichcha shakti.
They lack the desire to complete the action and their minds keep changing. Lethargy is manifestation of lack of ichcha shakti. A perfect balance of these shaktis is very rare.
Desire, awareness of the Self and action all are manifestation of the same energy that is you. One of these three dominates at a time. When desire dominates, awareness of the Self will be at its lowest. That's why all the philosophers around the world have always advocated renunciation and dropping of desires. When you are in a state of awareness, happiness dawns and when desire dominates, stress and sorrow take over.