Stop order is basically to put a stop in case you are in a loss and you wont lose all ur capital in case the coin you are trading dips down too low in a very short time. Anyways its upto the trader how he uses it but i think most people do not use it to it actual purpose.
That is exactly what is wrong with using stop orders. Stop orders are a nice tool when something goes down *in a long time* (like, at least 10min).
With a stop loss you CAN lose nearly all of your money. It happens during nearly all crashes, has happened, will happen again. You can check your exchange for spikes caused by large market sells, most likely triggered by stop orders.
The extreme case being selling your ETH for a few cents - you have pretty much lost all of your money, for a stupid reason.
And this is the case you describe - you are in a loss, most likely the market went bad, everyone is in a loss, all stop orders got triggered, if you're last in the chain, you're gonna get hit bad.
It has happened again for this crash, and it will happen again.
Go to Bitfinex, watch EOS/USD. There has been, again, some EOS bought at 3USD, and sold back immediately at 8USD. On which side do you prefer to be, the one who sold his EOS at 3USD? In any case this is a market sell. Most likely triggered by a stop. And it's not even just 1 idiot with a stop on a large amount, there may have been some little ones triggered after the idiot. That could have been you.
On one hand, I wish I had bought those EOS (no idea how much it was, but there was some volume there), sadly I had removed my orders 2 days before. On the other hand, if stop losses were avoided, "crashes" wouldn't be this bad, they wouldn't be automated, they would be human-driven and less instant, & thus probably less deep. But that requires everyone to stop using loss, or use loss-limit where available.
What you are guaranteed however, if the dip is instant, is to get maximum slippage. Noobs will think "I bought at 900, now it's 1100, I'm gonna place a stop loss at 1000, I will at least ensure a profit of 100". There is almost no chance it will sell at 1000, most likely it'll be around 950, *in this volatile market*. You'd better watch the order book before placing a stop, if it's very thin, 1 sell and your stop gets triggered way back.