I had my previous pair of sandals for at least six years which is a personal record for shoe ownership.  Most of my clothing has about 1/2 to a 1/3 of the lifetime of other people’s in that I don’t have any regular-wear clothing that’s older than 3 years mostly due to my chronic inability to act my size.  Additionally, clothing technology doesn’t really move at a pace that one really notices it from item to item in the same way as from say car to car or phone to phone but my shoe purchase interval in this case was enough.  I usually buy the 4th lowest price item that came in my size of 14D and in the style I wanted, which is non-fisherman (open toe) and not a flip-flop.  I was very happy with what I got as it contained 3 technological leaps that I just didn’t expect.

1) That stretchy zip-tie lace-up method thingy
2) A second side support to prevent blow-out
3) Some sort of nanoparticle-laced uber-sole that absorbs footsweat without getting icky.

Any of these would make me the envy of the subjects of King Herod or any Roman Centurion, but combined I’m at least on par with what the Olmecs or even the Rapa Nui could expect.  Your next, Mesopotamians!