Time is the most precious resource that you have. It is the most constant and available resource to a productive person. 24 hours of the day are what help increase the productivity of a determined and dedicated professional and contribute to the development of their company or corporate organization.
The unique thing about time is that even though it is always available you can never tell when your time will end. This is the biggest mystery with this resource that makes it even more precious as it is not predictable in the future.