Take off one of your shoes in a while and place it next to your bare foot.
You will see it immediately. Your foot is wide at the front, while your shoe tapers to a narrow point. Like a box that is too tight for what is inside it. There is often a heel underneath as well, which shifts your weight slightly forward, toward that narrow point.
Every day, you stand in a shoe with a different shape than your own foot. Hour after hour.
You don't notice it all at once. You notice it in the little things you start doing differently without realizing it: sitting down a little more often, heading home a little earlier, standing for a little less time.
Often, that is not your fault, but the fault of the box