The concept of having interchangeable, standardized parts is actually kind of a new idea from the Industrial Revolution. Before then, everything was custom-made to fit. The example that comes to mind is firearms. All of the muskets and rifles used in the revolutionary war, for example, were hand-made and hand-fitted. The lock from one rifle wouldn’t necessarily fit on another. If your stock broke, you couldn’t just go get a new stock and slap it on - you had to bust out the woodworking tools and make a new one.
You’re 13, and you just got out of the hotel pool, trying to remember where your family’s hotel room is at. Dressed only in your swimsuit and maybe a towel, shivering from the air conditioning, leaving wet footprints behind on the low-pile carpet.