I love things that last forever. My favourite is a gift from my late mother-in-law, who gave my wife and me her set of AMC cookware pots which she’d bought in the mid-1970s. We still use them daily. Almost 50 years after she bought them for what was then a large cash outlay, they’re still rocking and cooking.

This gets me thinking about the concept of cost per use, which I often consider when buying something, especially if it’s expensive...