Each stage consists the greatest essence of the previous stage.
STAGE 1: Work as Livelihood
When you work to earn money, to make ends meet, to take care of one's own and family needs.
Often this aspect grows into working for money, name, fame, power etc. However, here we are not talking about those degenerate forms. Though often times, even those degenerate forms helps one individualise and build one's capacities before one can truly offer and be of use to the world.
STAGE 2: Work as Passion
One works not just to earn one's livelihood, but out of a passion for what one likes and love to do, where one is coming alive. Be it shooting videos or dancing, the passion for that drives oneself.
At this stage, one is not very conscious of how one's passion is raising the consciousness or contributing to the societal well-being.
STAGE 3: Work as Social Responsibility
At this stage, one aspires to make a contribution to - the community, the society, the environment, the humanity. One is not just interested to see what one's own gifts are and how to grow them, but what the society needs and how can I can contribute to that. One begins to feel responsible for the state of affairs in the world and contribute to change that.
STAGE 4: Work as Service
Subtly different from Stage 3, herein it is not just about a sense of social responsibility and social change, but a heart that wants to give, offer and serve the Divine. It is no longer about "my ideas of how the world can improve and making humanity better off" but serving to manifest the Divine upon Earth.
For instance, from a social perspective, it may look building a hospital is a better cause and contributes to society more; but perhaps it could be in the Divine scale of things, a poet like Rumi's poetry is more impactful in shifting consciousness, inspiring generations after generations to act from a deeper space and perhaps build tens of hospitals as a result!
STAGE 5: Work as Worship
In this stage, there is not just action on the outside, there is a vast universe of action on the inside. The action of one's thought, inner voices, feelings, sensations. And each little detail of being is an offering, an aradhana, a service to the Divine. It is a very high stage, and perhaps, we do not even know what it truly means... All one can say is herein, there is no longer any difference between the inner and the outer, the self and the society. All is one flow of a Universal action. One is only an instrument.