I used to buy used tires. Until coming back from a trip I got two flats within the span of a couple of hours. I changed the one tire, but then had to get a tow in the middle of the night for the second one. And a motel room.
I figured new tires would be cheaper!
Those were adventurous times. Generally things like a tow or a motel room were out of the question. I still remember being able to afford a whole set of tires for the first time in 1979, even though the set cost over $200.
Nowadays I’ll buy tires as soon as the tread-wear indicators show, and a few years ago I even replaced an unworn spare on my pickup because it was about 10 years old. It’s quite a while since I had to change a tire alongside the road.