Reading list: Why is on-demand delivery often more expensive?
On-demand delivery usually costs more because it requires on-demand pickup and delivery teams to work in real time, with instant dispatch, priority routing, and dedicated resources. Unlike regular deliveries, on-demand services need faster drivers, live tracking, fuel readiness, and standby staff, which increases operational costs. Companies also invest in tech systems to ensure seamless on-demand pickup and delivery, adding to the price.
Conclusion:
On-demand delivery offers speed, flexibility, and convenience — and the higher cost simply reflects the extra effort and immediate resources needed to fulfil urgent requests.

https://fleetronx.com/on-demand-pickup-and-delivery/