The smallest permitted quantity can still be too small for an order.
At 18:42 UTC on October 27, Binance's BTC/USDT rules showed a minimum quantity of 0.00001 $BTC and a minimum order value of 5 USDT. At the observed price near 80,635 USDT, that minimum quantity was worth only about 0.81 USDT.
Both conditions apply. Quantity increments and minimum order value solve different checks, so rounding a quantity correctly doesn't by itself make an order acceptable.
At 18:42 UTC on October 27, Binance's BTC/USDT rules showed a minimum quantity of 0.00001 $BTC and a minimum order value of 5 USDT. At the observed price near 80,635 USDT, that minimum quantity was worth only about 0.81 USDT.
Both conditions apply. Quantity increments and minimum order value solve different checks, so rounding a quantity correctly doesn't by itself make an order acceptable.