Ozone and other elements in the air around us just seems to wear at the "ductility" and composition of the soles (and maybe our souls, too ;^))) ).

I have some hiking boots that turned into sticky goo (neopreme, quality boots) a few years ago.

I decided to buy canvas Top Siders and ONLY use them on the boat (not as street of even dock shoes). They were the classic soles that hold like glue.

After two years, you might as well be wearing new leather soles on a waxed floor -- really dangerous.

One thing to be careful of are you wet boots. Check those before that dark and stormy...