Sometimes you want a ride right here right now, other times you want "a ride to the airport at 6am tomorrow".
Uber let's you "schedule rides" but that doesn't actually do anything to guarantee a ride. You could wind up without a driver if you're unlucky.
Directly contacting the person driving you, 12 hours in advance, is a much better way to guarantee a ride.
...if they haven't had any car trouble, and haven't quit providing car service, and are intending to work then, and haven't scheduled another ride for the same time, and are willing to schedule something when they don't know where their unscheduled fares are going to leave them just before.
The apps that match workers with customers are actually doing something useful. The main problem is that people keep trying to get them to be considered employers, which increases their costs, and then those costs get passed on so that more of what you pay goes to overhead and less of what you pay actually goes to the worker.
I suspect that delivery apps crafted a moat by building a network effect with cheap prices, and now people just use them out of habit. If you know what kind of food you want it can be cheaper just to order directly from the restaurant, and you often get better service. Our local Indian restaurant has a 10% discount for directly ordering through their own app website instead of a delivery app.
Same for food delivery.
Very different for a cleaner: you never need a cleaner "right now", you can schedule it.