I am not scammed by any exchange rather than I am making some money as profit for making successful trade. Still I am a trader at Binance and Bittrex. Both exchanges are good enough and I am much more happy for their user friendly interface and smooth UI. Still I have almost $1k++ on Binance exchange and I am happy with their volume. You must have to be careful when you are going to deposit. There are many reasons behind that you claimed. I can't tell the exact reason. But I can say that I am happy with exchanges which I mostly used. I strongly believe that there are many exchanges in the world which give the customer's optimum service and priority.