It's way more effort to order with a phone app than to just roll up and tell someone what I want. That's all there is to it, really.

My experience is different. If my wife goes to the counter and I order electronically, she is always done faster. This is doubly so if I use a phone app, because the app is painfully slow.

If it was just slow, I might put up with it. But the systems are broken. For example, it's recently changed, but the electronic order screen in the restaurant used to print a receipt with an order number. The bulk of the time the printer was didn't work - out of paper or something else. Then you had to remember the order number, or have an argument with the counter staff, or on occasions both.

The app is anything is worse. On several occasions I've had the app not clear my previous order after collecting it. I didn't notice. The result was a double order the next time around. If I did notice, it would take ages to clear the order because the app insisted you delete the items one at a time and it's takes seconds for each item. On one occasion I drove up, gave my app code to the cashier, only to have the restaurant claim they had no record of the order. I showed them their app on the phone saying it had been paid. They said they could not trust it. It took me 30 minutes on their web site to get the payment refunded.

One restaurant has recently fixed the printer receipt problem. They get you to enter your name now, and they call it out when serving the order. The printer has gone. It took, what, 5 years to recognise the problem and find a fix. I assume the same will happen with the app, but I'd expect another 5 years at least.

The reason the cashier is faster is partially because the app is slow, but also because the UI is different. The user friendly interface displays long lists with nice pictures the user has to navigate by scrolling. The cash register UI is designed for speed. It displays lots text buttons that near respond instantaneously. They could streamline the app interface a little, but you will never be able to hit the speed of a experienced cashier entering the order, or an AI doing the same thing. The app using an AI to process your voice order on the other hand could be just as fast. Maybe that is what we will get next.

It seems hard to have empirical data here, but even just the parallelization of it seems to bias in favor of mobile ordering.

Part of the reason I hold this particular opinion weirdly strongly is because of the confusion I feel when I'm sitting in line in the drive-thru behind a van where a family or a group of friends is trying to crowdsource food for 2-4 people live at the window, or rattling off a complex coffee order and hoping the audio quality carries it through.

If you're ordering something different every time, and not anything complicated, and it's just you ordering, and the tech in between you and the person listening is decent, I'd bet that you're right and just telling someone your order is less effort. But as soon as there's any stray variable, mobile ordering handles the complexity much more smoothly.

Some places, like ChikFila, seems to optimize their drive thru experience. That said the trick that I do with them is say that I’m at the restaurant well before I get there so I don’t have to wait.

I have a different experience. For places I order from semi-frequently (Taco Bell, Burger King), I have favorited all the things with the customizations I like from previous orders. Then it is a tap or two away from being re-ordered. Super useful too when I am always doing similar but repetitive modifications every time (eg taco bell, beans for meat, fresco style).