The Wall Street Jungle, written by Richard Ney in 1970, compares the field of investments to a shadowy, sometimes impenetrable wilderness filled with dangerous beasts and hidden treasures. Blindly venturing into this unknown world can easily end in disaster.
Often, predators such as con men, thieves, and bandits lurk and set traps for overconfident, naive adventurers foolish enough to believe that a free lunch is possible. Inexperience can lead to a failure to recognize risk (or underestimate it) and result in poor decisions and financial loss.
However, overconfidence is more often the cause of investment catastrophes, especially when coupled with the innate tendency of people to follow the herd. In his 1871 book The Descent of Man, Charles Darwin writes, “Ignorance more frequently begets confidence than does knowledge.”
More at: http://www.moneycrashers.com/worst-dangerous-investments-hurt-financially/