Maybe it’s low margin.
Maybe cleaning is expensive.
Maybe it helps having the promise of cheap ice cream but “sorry not right now” leading customers to buy other (more expensive) items.
It’s not an incompetent organisation.
If they wanted the machines to work, they would work.
They don’t.
So… if anything changes out of this, it will be to keep the status quo; people coming in and not buying cheap ice creams.
If anything, ice cream products represent a very profitable item that often serves as an upsell helping drive the APV (average purchase value) higher.
Milkshakes in particular have a unique "job to be done" in the drive-thru fast food industry: https://hbswk.hbs.edu/item/clay-christensens-milkshake-marke...
They can be eaten easily in the car, can be savored slowly over time on a long commute, and are relatively filling and inexpensive. There are a lot of people who actually consume them earlier in the day before work because of those characteristics.
You'll notice that basically every burger chain offers milkshakes, and some even emphasize the shakes more than the food, like Shake Shack, Dairy Queen (which has quite good fast food burgers and food if you aren't aware), and Steak 'n Shake. They all do this because it's an extremely profitable product and a driver of high APV.
The ice cream machines at McDonald's also deliver multiple products: McFlurry, hot fudge sundae, milkshakes, and ice cream cones. One small machine that dispenses vanilla soft serve can make a whole bunch of products.
Your analysis posits what, that they’re just blatantly incompetent?
I don’t believe that.
If the economics of a working ice cream machine were that good, it would be a solved problem.
You don’t run an organisation like MacDonalds with a basic inability to maintain infrastructure. Imagine if that was true of fryers? Or microwaves? That almost never happens. It’s clearly not a technical problem.
The only way that you could justify the continued maintenance failure you see is if the benefits of a working machine were negligible at best.
Perhaps what you say might be true in general but in this specific circumstance I think you’re applying an “in general…” kind of logic (like “in general more unit tests are better…”) which doesn’t ring true here, to me.
Dump the liquid in the machine, turn it on, empty and clean the machine at close. There's almost nothing else in the store that is so low-effort.
I'm not saying that the high rate of failure isn't a problem or lost revenue.
I also have a hunch that the problem disproportionately affects specific franchise owners who benefit from the product less than others.
First, the ice cream machine produces multiple products: milkshakes, McFlurries, hot fudge sundaes, and ice cream cones.
Second, dessert is an upsell and driver of APV. If you lack dessert options you basically leave money on the table from customers who are willing to buy dessert.
Third, the ice cream machine, despite its problems, is a pretty small and manageable piece of equipment. It doesn't need an employee to babysit it like a fryer or flat top. The only thing simpler at a McDonald's is the Apple Pie heater.
If you don't believe me, find a burger chain that doesn't have ice cream on the menu. Wendy's, Burger King, Shake Shack, Steak 'N Shake, In-N-Out, Whataburger, Culver's, Carl's Jr/Hardee's, seriously, which restaurant that serves burgers doesn't have ice cream/milkshakes?
This is never going to happen.