I’ve driven a little around Portugal, and their roads were the worst I’ve ever driven on. Not just potholes, but the roads were often wonky and/or not flat (think like undulations like waves as you’re driving along), missing road markings etc. The quality drop was really noticeable when you drove from Spain into Portugal. It was about 8 years ago so it’s possible they’ve really got their act together since then, but I’m skeptical about how reliable their data is if Portugal is listed as the country with the 5th best roads in the world…