[Piskvorrr]

Roads are dirt-cheap (pardon the pun) compared to rail: first off, a road requires an order of magnitude lower precision, can scale significantly steeper grades, and allows for curves and stopping distances that on rail would be considered insufficient. Next, operating it is a dark art in itself - scheduling, communication, safety, etc.; a highway through nowhere just needs asphalt and it just lays there, a railway needs active elements. And to top it off, there's maintenance: a 2-inch bump in a road is normal, in a railway it's a major defect. Worse, rerouting around a closed section is not a simple matter of setting up traffic cones.

All of that is expensive - like the difference between 80% and 99.9% reliability.