GP means that TEMU is just the marketplace. They aren't actually selling you the drill, just facilitating the sale.

If someone says to you "You can buy this widget that costs $10 to make for $5" that doesn't mean they they're selling it for $5. It means there's more going on and that the $5 price take is not the full story.

You may choose to ignore that and believe someone is selling you something for $5 but that doesn't make it true.

In the case of Temu, they're selling it for $5 of your money, and $5 of someone else's money, in order to capture you as a customer in the hope that you continue to buy things when they increase the price to $6, then $8, then $10, $15, $30 and so on in the future.

This is the Uber playbook, and if you have a solid product that people want and you can spend VC money long enough to build a trusted brand (or ideally keep prices artificially low until the competition gives up and you have a monopoly) it's very lucrative. I don't see it working for Temu myself. They sell things people don't need so as soon as the prices go up they'll probably fail. That said, Amazon see them as enough of a threat to launch Haul, so what do I know?