My carry-on is about twenty years old. It’s a Rimowa Topas — aluminum, scuffed to a dull shine at the corners, a couple of dents I could name the cities of.

No stickers. Stickers try too hard. The two wheels are exactly where they were bolted two decades ago. That part is the whole argument. I’ll get to it.

Two wheels is now a strange thing to want. Rimowa stopped making the two-wheeled Topas years ago, doubled the price of what’s left, and would much rather sell me a spinner: four wheels, each on a swivel, the bag gliding sideways across the showroom floor like it’s auditioning. Everyone makes spinners now. The clever new brands ship nothing else. Briggs & Riley, bless them, still list three two-wheelers against eleven spinners on their carry-on page. I checked the count this year the way you check on an elderly relative. Still three. So I ordered another one.

The case against the spinner is mostly physical. To let a wheel swivel, you mount it in a housing that juts past the corner of the bag, or you hollow out the inside to make room. Either way you lose space on a bag whose dimensions are fixed and every inch already spoken for. And because the wheels have to tuck under and spin, they’re small. Small wheels are worse wheels. A big wheel rolls over the gap; a small one drops into it.

Then there are the cobblestones, where the joke finishes itself. Watch anyone cross a European old town with a spinner. They tilt it — they have to, the little casters chatter and catch on the stones — so they drag it along on two of its four wheels, exactly like a two-wheeler, except now they’re rolling on the two smallest, worst wheels the design could manage. They bought four and on the one surface that tests them they’re using two. The feature folds the instant the floor stops being polished.

There’s more, and I’ll spare you most of it. The protruding casters are the first thing to go when a baggage handler stacks your bag wheels-down in the hold, which he does, in the dark, where you never watch it happen. And a spinner won’t hold still. The top of a jetway, a sloped curb, the deck of a train pulling out, and off it goes across the floor while its owner lunges after it. Mine stays where I put it. It has no ambitions.

I’ll give the spinner its due, because it has one. You push it upright instead of dragging it behind you, which is easier on the wrist and the shoulder, and for an older traveler, or anyone with less grip strength, that’s not nothing. It’s a kinder bag. But if easier-on-the-body were why the spinner won, the people who move a bag every single day — the flight crews, the ones who live in terminals — would have switched first and hardest. They didn’t. The rollaboard was invented by a working pilot. The people who do this for a living are still, quietly, on two wheels.

So I don’t think the spinner won because it’s the better suitcase. I think it won because it’s the better suitcase for the thirty seconds you spend with it in the shop. Everything it does well, it does on a flat clean floor under good light — the floor you happen to test it on. Everything my bag does well, it does later, somewhere the shop can’t show you: in the hold, on the cobbles, on the hill, across twenty years. The showroom is the spinner’s whole case. It’s also where the sale happens.

I know how this sounds. I’m aware that I am, in the end, defending a wheel count. The world has four wheels now and it isn’t coming back for me, and I find I don’t need it to. I’ve got my dented Topas and three survivors on the Briggs & Riley page, and on the day that three finally becomes zero I’ll do what cranks do. I’ll go to eBay and outbid some other crank for a dead stranger’s two-wheeler — ideally a scuffed old thing with a logo from an airline that stopped pressing them. I’ll pay too much for it. I’ll be delighted.