How to check for wear
Heels: If you look from the side of the heel, you
can see the toplift. Follow the seam between the toplift
and base to the rear outside border of the heel. When you
are down to the thickness of a dime in that area, it is
time for new heels, and you have avoided damage to the base.
If you wait until you see the light-colored base at the
rear outside borders of the heels, you are causing unnecessary
damage to the base.
Soles: Do not wait until you see a hole. In many
cases, if you turn the shoe upside down you will see wear
in a circular shape. In other cases, you may not see the
wear, but try pressing the center of the sole with your
thumb. If you feel weakness or sponginess, it is time to
replace the sole and you haven't caused unnecessary damage
to any other components of the shoe (such as welts, insoles,
or sock liners).