Stuart saw this promotion ad, giving bonus for depositing and trading cryptocurrency, he thought that by depositing money, he is actually purchasing Etherium, the truth was that he was just gambling the Ether rates inside a manipulated trading platform.
Once the trading platform account manager understood that Stuart wont deposit anymore money, he lost everything that he had on the account.
Please be sure when you are depositing money to an exchange that you will receive the coins to your personal wallet, and no one besides you will have access to trade it.
The value of Currencies wont get to Zero, it can go up and down but almost never disappear,
while when you gambling on rates in an inner platform you can lose all of your investment.