| Well, let’s consider a simplistic example: an obscure currency, let’s call it FAKE, that can be traded for USD. That currency is only used by people in a small island, and that island only exports clamshells and imports Big Macs. In this scenario, and unless I’m mistaken, the FAKE/USD rate will vary depending on:
- how much clamshell those people can export and how much US people value them
- how much BigMacs those guys import and how much those guys value them Enters a day trader - someone who will never buy a Big Mac nor any clamshell. The guy speculates and there are two possible outcomes : - He fails. Technically he basically gave “value” to either USD holders or FAKE have holders. Too bad for him, but he kinda made this happen. - He succeeds. Now what? Isn’t that kind of a parasitic behavior? Couldn’t that be considered theft to some extent? I guess the question may boil down to “why would they even let the day trader be part of this?”. |
There are two ways to make money as a pure market player: connecting buyers and sellers who wouldn't trade directly (and taking your cut) aka arbitrage, or getting paid to take on risk. Maybe the trader notices that people on the far side of the island are hungry but can't get a big mac without a long walk, so he buys as many as he can carry, walks over to the other side of the island, and sells them for a bit more than they'd cost on the dockside - that's the first kind of trading. Maybe a clamshell farmer wants to make sure they can afford enough big macs over the next year. They might agree to sell their next year's clamshell harvest at a fixed price (that's lower than the average), or buy their big macs for the next year at a fixed price (that's higher than the average), or both; the farmer loses value on average, but they offloaded their risk, while the trader makes money on average but has to carefully manage their risk.
The third thing is to actually take an active position in the market, if you can predict what's coming. E.g. if you realise the clamshell harvest will be big this year, maybe you sell a bunch of clamshells short. That should send a useful signal to all the farmers, and it means you make money if you predicted right.