Roads are modified and maintained, but only in a completely ad-hoc manner. So some localities have good roads and maintenance, and others have terrible roads a

Roads are modified and maintained, but only in a completely ad-hoc manner. So some localities have good roads and maintenance, and others have terrible roads and maintenance and even road design. You can't expect any kind of consistency, because roads are mostly handled at the local level in the US, and many localities are completely incompetent, or refuse to spend any money on it. What you're describing would require consistency, and that's a completely impossible expectation in America.