On one side of the agreement, you undertake the great idea of your invention that is not previously known by the public. In return by the patent being granted by the government, the public provides the agreement that you have up to a twenty year monopoly period to exploit the invention. At the end of this period, the public is able to freely use your invention.
Thereby the agreement with the public encourages inventions which aid the public. It also rewards inventors.
Patents are assets like houses. The asset of the monopoly to exploit your invention can be sold – like a house. The asset of the patent can be licensed for others to use your patent while paying you a licence fee- like renting a house. Also there can be other ways of commercially exploiting your patent asset.
Thereby the asset of the patent allows you to profit from your invention.
By having a patent you are able to negotiate with big enterprise or with big financiers. Instead of just having a great idea or invention and being commercially swamped, you have a monopoly for up to 20 years to commercially exploit. This could allow you to negotiate even though you do not have the manufacturing or distribution power or capabilities. Alternatively, it can be a tool to give you a head-start in business by preventing others using your idea as protected by the patent.
Thereby you have a tool to enable you to be part of the commercial world on a strong footing.