traders are undercapitalized so they overtrade their accounts.
Now imagine world without leverage to trade 1 lot EURUSD you would need 100,000 EUR account just for margin,
yet the profit would be the same like trading 1 lot EURUSD on 1,000 EUR account.
So without leverage we are risking that 100,000 EUR as everything can happen and is happening on Forex. So ANY funds you deposit to your broker are at rsik.
With leverage we are risking just that 1,000 EUR.
The profit and losses are determined by stop losses and take profits, not the leverage.
In our example if we put 10.0 pips stop losses and take profits we are losing or getting just $100 in both cases.