Why was buying stocks based on speculation a risk?

Yes buying stock on speculation was a risky because the one who bought the stock depended 100% on a rising stock market value to get his or her money back.

Explanation:

Because of lack of support and no security such types of stocks were very sensitive to buy. A type of risk when ventured outputs in two things either profit or loss. In the investment world most of the activities involves some sort of speculative risk.