Generally rail + last mile truck is cheaper. It takes longer however, which increases capital costs: goods stay in container for longer, so you need more of it

Generally rail + last mile truck is cheaper. It takes longer however, which increases capital costs: goods stay in container for longer, so you need more of it to fill the ‘longer’ pipeline so to speak. And there is the issue of economics, the owner of the container is generally the shipping line, which will give you a relatively short time to deliver the container empty again after pick up in the port. This is called the detention time. After the detention period you pay extremely high fees per extra day the container is in use. The incentives of the shipping line are very much not aligned with that of the receiver of cargo: the shipping line wants their container back in stock asap, the receiver wants the cheapest hinterland transport.