On interstates there are several kinds of roughness.
One would be potholes, which I suspect are most common in northern states, where ice, salt, freezing etc breaks up the pavement.
Another is wear grooves caused mainly by heavy truck traffic. Some try to fix that by grinding it flat, and adding a new layer of asphalt.
The worse is tilted slabs. Again heavy trucks are a major factor. If the ride is bouncy this is likely the cause. Fixing takes more work, such as actually realigning the slabs and adding dowels of some sort to keep them aligned. I believe this was worst when the interstates were a few decades old, and most states have already addressed this.
Bridge expansion joints also need to be replaced - this may be the most common work you'll see.
Roads, and all infrastructure, are built with a design life. I've seen references to roads with built with a 25 design life, and are still be used (with patching) after 50 years. Total rebuilds are expensive, and very disruptive to traffic.
Got to a state's DOT website to see what construction projects are in the works, or have been recently completed. Alabama DOT shows quite a few, but I can't say how that compares to other states. Streetview images of I59 don't suggest anything unusual. It looks relatively flat and wide, without unusual traffic. There aren't any obvious potholes, wear grooves, or tilted slabs. Though it is possible that the asphalt overlay hides problem slabs.
