Leather dries out over time when left to sit and becomes brittle. It must be treated with some thing like a leather oil rub or “saddle butter”. Fake leather is similar.

When you wear them regularly from new before they dry out, the sweat and oil from your skin goes a long ways towards keeping the leather pliable.

Artificial fabrics obviously don’t have this problem, unless exposed to sunlight.

Leather needs to be maintained (oiled or polished), even if you’re not wearing them.

Polyurethane (PU) will gather humidity by hydrolysis in storage if not used regularly, especially if stored airtight, and will crumble in half an year.

It’s used as sole material in sportswear, Scandinavian outdoor and military gear, and several Indian shoe manufacturers. Especially the military boots are funny, because they literally crumble off the shelf.

Also used as vegan / synthetic leather and has to be dried properly if wet.

Take good care of your gear.

Fast fashion is disposable garbage not made to last