Construction/architecture-metaphors work a bit too: They can outlive the involvement of the initial designer, many bits can be tacked on or changed, and they have some overriding functional requirements.
They especially work if you've owned and maintained an actual, physical building. You can build for the ages, but if no one patches the holes in the roof every now and again, it will rot from the inside out in a few years.
Most long-lasting stone structures are in constant decay. Without being weather sealed and maintained, they will decay and fail. Even if they are in moisture and vegetation free environment like the pyramids, they are still subject to that most basic human trait - theft.
Architecture metaphor is relevant because architecture is a mix of art and science. The same happens with software.
Very few houses become or have the pretension to be monuments. Most of them only have a mundane function: they are shelters. The same happens with software.
Very few architects are visionary enough to project an house in a different way and point a new direction. Most of them just follow the existent trends. The same happens with software.
Most houses become monuments because of historical reasons, not because they are the best ones. The same happens with software.
