You can lose profit sending trading and withdrawing if you are trading a small amount I have $50 worth of Ferum or FRM it will take $6 to send the whole amount to Bilaxy and after you trade it to Eth and wants to withdraw it you will have to spend $12 to withdraw your Eth,
now that's $18 gas fees for your $50, my only option is to trade it to other altcoins like DGB or Litecoin which offer $4 to $5 fee you still going to lose $11, that's over 20%.
This is unfortunately true and there is nothing much we can do about it. The only hope is the implementation and activation of the eth 2.0 that will make the network fast and cheap but for that we still have to wait for few months.