I remember a wise old colleague saying to me "As I get older I get more and more certain about fewer and fewer things". I find it interesting how many things were once central to my belief structure or identity just don't seem to matter much any more, but there's that handful of things I'd fight tooth and nail for.
I would imagine that in your youth you build a simple structure from what you judge to be good materials, a structure that will stand strong and provide a foundation for your perceptions to dwell in. You don't have much at hand at the moment, but this is going to be the base of whatever it is you build, so it must be sturdy. Appearance-wise it will be limited. As you live your life and experience a variety of things, you build on the original design more and more, taking it off on tangents, experimenting here and there, and that original stark, strong but limiting structure becomes lost under an eclectic collection of design features and interior decoration that is comfortably diverse and wonderfully confusing. You don't need to be so certain and sure now, because you've long had a home where you once were building a house.