How ordinary OSRS trading works
The in-game trade window is sound for swapping items for items or gold. Both players offer their side, both accept on two screens, and the swap happens at once: either everything moves or nothing does. Most in-game scams try to get you to trade outside that window, or to accept the second screen without reading it.
The window cannot help when one side of the deal is not in the game, such as real money, or happens later, such as a service. Then somebody has to go first, and whoever goes first is trusting the other person.
What drop trading means
'Drop trading' is used for two things. One is moving items between accounts by dropping them on the floor for the other player to pick up, usually to get round a trade restriction. The other is the looser practice of handing over items or gold first and trusting the other person to pay or return the favour.
Both are fragile. Dropped items become visible to other players after a short time, and anyone can pick them up, including an account waiting nearby for exactly that. Handing items over on trust has no safety net at all: once the trade or drop is done it cannot be undone in game.
Trade restrictions usually exist for a reason, and getting round them with drops to complete a real-money deal is still real-world trading, which breaches Jagex's rules however the items move.
The scams built on 'you go first'
Trust trades: someone promises a large reward if you lend them items to prove you trust them. They log out. The trust test is the scam.
Fake middlemen: a third player or a Discord user offers to hold both sides. They are the scammer, or are impersonating someone known. A legitimate escrow trade never needs a stranger holding anything.
Pay-first gold deals: a seller asks for payment by a method that cannot be reversed, then never trades. The mirror image hits sellers: a buyer pays by a reversible method, receives the gold, then reverses the payment. Selling gold safely covers that side, and our scams guide lists the rest.
How escrow answers 'who goes first'
On this marketplace the buyer's payment moves into an escrow hold when they order. The seller can see the order is funded before they log in, so they are never trading against a promise. The seller then delivers in an ordinary in-game trade, usually at the Grand Exchange on a members world agreed in the order chat.
The money is released only when the buyer confirms delivery. If something is wrong the buyer opens a dispute instead, and the release is frozen while a person reviews the order and its chat. Neither side has to go first on trust, because the money is already secured and cannot be pulled back by either of them.
What escrow does not do is make the trade acceptable to Jagex. It protects the payment between two people and nothing else.
Habits that keep you safe
Read the second trade screen every time. Never lend items. Never trade on the promise of a reward. Keep every agreement in the order chat rather than on Discord. And be most wary of anyone pushing to move a deal off-platform, because the only thing that move achieves is removing the record and the hold.
If you are buying, the gold category and the full marketplace show listings from ID-verified sellers; if you are selling, selling OSRS gold explains how a funded order protects you.
The short version
Drop trading and trust trades fail because somebody has to go first. A funded escrow hold removes that: the money is secured before the trade and released only when the buyer confirms.