There are a number of factors, but the simplest gist: 1. The models for road funding and development were developed in the 1920s and 30s, were based on much de

There are a number of factors, but the simplest gist: 1. The models for road funding and development were developed in the 1920s and 30s, were based on much denser areas (old towns) that paid a lot higher taxes per acre, and much simpler roads (which cost a lot less). 2. The models haven't been significantly updated or reconsidered since, even though the development patterns have been mandated by law to become much less dense, while street standards have also greatly increased, meaning much less tax base to support much more infrastructure. 3. This often pencils out in places that are growing because there are heavy state and federal subsides for "growth" projects where the up front capital cost is 80-100% paid for by non-local funds. That infrastructure works without maintenance for a while, and likely won't need heavy maintenance for 20-30 years, but at that point it'll need to be rebuilt at about the same cost adjusted for inflation as it cost to build. In theory what should be happening is cities should be piling up money from taxes on these projects that were subsidized, so that when the maintenance bill comes due they have the funds to do the maintenance. But in practice, the taxes that come in from "today's" new growth are used to pay for the maintenance on "yesterdays" old infrastructure that needs to be replaced. Thus, things appear to "work" as long as steady growth continues and new tax income continues to be generated locally while the costs associated are funded from outside. But when growth slows down or stops, things quickly break down. You can see this pattern of "rolling blight" all over the country, where so many of the older suburbs are falling apart with decaying infrastructure, and people who can are moving farther out to the "shiny and new" suburbs where everything is in good shape. The problem is especially pernicious in the rust belt, where we have seen metro areas dramatically expand in surface area every decade even as their population has barely increased (or shrunk) since the 1950s.