I suspect that the useful lifetime of running shoes depends upon the runner's weight. As a heavier runner/walker trying to control my weight, I found the 500 mi/pair to be reasonable when running.
I could walk longer in them w/o problems. I'm currently rehabbing a strained hip and walking 35-40 mi/week and need to replace shoes about every 750 mi. I suspect a lightweight runner could get a longer useful life from the same shoe. Like many others, I have found the uneven wear patterns on my shoes reflect issues with my foot strike that I have improved but not eliminated.
Lighter is probably better, to be sure. Less mechanical stress per step. Faster generally means less steps per mile, and being lighter often means being faster too so it's a double bonus. Maybe I could wear shoes twice as long if I lost twenty pounds. But I think we all know by now that weight is more affected by diet than exercise, so there are a lot of us "Clydesdales" out there.
P.S. For any who don't know, "Clydesdale" is a real running term at least in the US. Many races let men over a certain weight (e.g. 185 pounds) register in that division instead of their normal age group, with its own leaderboard etc. "Athena" or "filly" are slightly less common equivalents for women.
Same, though. Although I was reasonably light (~85-90kg) when I spent a year running on the same shoes. Currently on 1250km (mix of run/walk) for my Hoka Bondi and I've been considerably about 85kg for all of that.
I could walk longer in them w/o problems. I'm currently rehabbing a strained hip and walking 35-40 mi/week and need to replace shoes about every 750 mi. I suspect a lightweight runner could get a longer useful life from the same shoe. Like many others, I have found the uneven wear patterns on my shoes reflect issues with my foot strike that I have improved but not eliminated.