We all know that we need to spend our money wisely. What may be difficult to keep in mind is that every dollar spent is yet another piece of our future we lay.
As advice blog Raptitude points out, there is a finite amount of money that any of us will ever be able to spend in our lives. While that number is unknown, and varies from person to person, it's still limited. Treating that pile of cash as the building resource that it is can be a perspective we all need:
Every expenditure comes out of a large but finite pile of all the dollars that will ever be available to me, not a running pipeline that comes from somewhere out of sight. My mentality now is to build something with my dollars, rather than fuel something with them. The thing I'm trying to build is a life that's set up to generate happiness on its own, as an inevitable byproduct. Every dollar I burn -- rather than place somewhere where it will contribute to my happiness for a long time -- is a lost opportunity that will affect what I am working with for rest of my life, to some degree.
In general, people are built with a pretty crappy sense of future consequences, so it's no surprise that many of us don't default to this mindset. However, having a concept of what you want to build can help.