Value created by transaction order
The order in which transactions are processed within a block can affect execution prices and fees. Maximal extractable value (MEV) describes value available through selecting, inserting, or reordering transactions during block production.
How inclusion order is chosen
transactions visible in a public pending queue can be observed by validators or specialized participants, who may alter fees and ordering to pursue arbitrage, liquidations, or other opportunities. The effect differs by a chain's consensus and market design. A displayed estimate assumes conditions at one moment, so it should not be treated as identical to the final execution, settlement, or withdrawal result.
Costs that can reach the user
a large swap or liquidation can be bracketed by other transactions and receive a worse outcome than expected. Paying a high fee does not guarantee a fair result, and private order routes introduce their own trust assumptions. Consider separately the cases in which price moves, network congestion, shrinking liquidity, and a change in operating authority happen at the same time.
A hypothetical swap in a shallow pool
A large buy swap in a shallow pool can be surrounded by another participant buying first and selling after the target transaction, worsening its price. A minimum-received limit can constrain an unacceptable outcome, but it does not control transaction ordering or remove failed-transaction costs. Review order size and pool depth as well.
Limits of protective features
review the minimum received amount, trade size, liquidity, order route, and wallet warnings. Do not read a technical term as a return promise; include failed and retried transaction costs in the decision. Match official documentation with the on-chain address first, and avoid connecting a wallet through search advertising or a link with a similar name.
How transaction order can change execution
In a shallow pool, trades inserted before and after a large swap can move its execution price and then reverse the move. A minimum-received setting limits acceptable output but does not control transaction ordering or remove failure costs.
Conditions to check before trading
To assess ordering risk, consider order size, available liquidity, minimum-received limits, and the protection route being used. Those features do not remove every failed transaction, delay, or fee, so verify their documented scope.