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%.
Same here, I do the same thing most especially since Ethereum’s price has increased. I also trade them to other coins like DGB or XRP for lesser transaction fees. At least the your loss wouldn’t be that much as of Eth’s gas fees.