Is it a metaphor (spoilers)
They build the town and later they undermine it (literally) leading to the destruction of all they have accomplished.
- Maybe the people who have an idea and realize are not the best people to maintain it? (Like the way Steve Jobs later was ousted from his own company.)
- Or humans in general are their own worst enemies sometimes?
- Or the dangers of building things too quickly and without proper foundations, here both literally and communitatively in the sense of having no proper planning, or legal underpinning.