I don't really understand why you say that!
investment in stock is generally considered a smart long-term strategy. I know it's not guaranteed, but it historically offers one of the better risk-adjusted compared to other assets.
Trader 1 trades almost only AUDCAD with high volume, showing big swings but still staying overall profitable. Trader 2 spreads trades across many pairs, and shows steadier performance.
I can't think of a situation where using a leverage even close to 1:10,000 would be wise. The highest I would ever go for would be 1:1000 though the broker I work with offers double that amount.