Lol, I was once into this but learned the hard way later, the fact is there are other things that may delay you from earning with this strategy, buying less on a exchange and selling high on another don't always go smooth, sometimes you will be stuck due to slow withdrawal and before the transaction go through the price would have adjust
That's the risk to consider, it would be acceptable if the price will not dump even if there's a maintenance but if they intentionally do that, then you have no choice but to accept their loses, sometimes we think we found an arbitrage opportunity and we thought they don't know it, but in reality it's just a trap to attract us to buy their coins.