At its most simplification, Money is an exchange for work and time.
That is… Work * Time = Money
As a people, as a society, community we agree and participate in this exchange. Trying to regain our own time in exchange for someone else’s work and time.
(Work * Time) Rate = Money
The “Rate” is the variable, effected by supply and demand of the skill. How many people can do the skill versus how many people need the skill. The scarcity effected by what we invest ourselves in, education, experience, knowledge, expertise. The more development and advancement puts them in a smaller set of people that can do the job, limiting the supply.
We need this exchange, not everyone can be an expert at everything. When we require a service or product, we are paying for their expertise, ability, knowledge, experience. This is the great interchange of a society. The need for each other. People seek their own abilities with passion, necessity, development, experience, knowledge. And other people seek those people for their expertise, experience and knowledge. And vice versa. The plumber, baker, writer, doctor, we are all on an interchange with each other.