I think a very important point is how much the investment is in terms of one's net worth.
If there is any chance of loss of capital, one should not bet more than they could afford to lose.
Why? Because that leaves one in a financially desperate situation.
So one needs to guarantee preservation of a comfortable amount of capital.
Even if it were a small amount, though, I will take a guaranteed 25% gain in let's say a 2 year period over an investment with a 10% chance of losing it all.
If you are talkiing about a 25% gain in a 10 year period, I can do better than that with high quality bonds which have only a 1% or less chance of default.
You are aware, I trust, that financial advisors recommend that young people take more risks with their portfolio than old people. Just because it is harder for an old person to recover from a big loss than a younger person.
I don't think young people should be taking big risks either because I think it is important to build the financial asset base over time.