How good are American roads?

Anecdotally, I once shared a house with a Russian student in Monterey, California. He told me he was amazed by the quality of our roads compared to those in his homeland, though I don't recall which part of Russia he was from.

I grew up in rural California. Despite living quite remote—about 25 kilometers from the nearest town—by my standards our main roads were well-maintained. However, numerous smaller side roads branching off to serve sparse residential areas, sometimes leading to just a handful of houses, were another matter. I wonder if California has a larger proportion of these minor roads skewing the results. Yet paradoxically, two major urban centers, San Francisco and Los Angeles, are it would seem quite terrible.