system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How can it be profitable for AliExpress merchants to sell and ship an item across the world, for just $1

It blows my mind why anyone would do it, when you gotta factor in order processing, delivery to couriers, the shipping services, etc.
gpt
Think of it as there is this container already planned to go your city, on a specific date, from the shores of South China. It is booked on every ship, train & lorry it needs to get there. The company merely puts your extra item in the container.