Market mode allows you to convert your assets at the current market price based on the quoted price in the conversion.
Limit mode allows you to place an order to convert your assets at a specified limit price. For example, if you place an order to convert USDT to BTC at a limit price of 9,000 USDT per BTC and the current price is 10,000 USDT per BTC, the order will only execute when the price per BTC is 9,000 USDT or lower.
Similarly, if you place an order to convert BTC to USDT at a limit price of 11,000 USDT per BTC and the current price is 10,000 USDT per BTC, the order will only execute when the price per BTC is 11,000 USDT or higher.
Limit mode orders are executed subject to market conditions and may not be completed even if the market price reaches or crosses your limit price momentarily.