Arrogance is to say it'll never happen to you.
Yes, there are a number of common themes to all such cases when looking at news stories written after the fact with the benefit of 20/20 hindsight. Generally in the real world it doesn't start with "We'll double your money for you, overnight" but with something a lot more plausible that is maybe slightly better than your average return.
Never forget that a) Fraudsters make a living by being convincing and b) they've got a lot more experience at conning people out of money than you have of avoiding cons.
Also while y'all are being quick to judge, remember than fraudsters are every bit as much a criminal as your burglars, yet we put no pressure on politicians to deal with fraud, precisely because of the arrogance displayed above - everyone believes they're too smart to be conned, until they are (in the same way that everyone thinks they're an above average driver, or if you've ever left anything valuable on display in your car, you deserved to be robbed). The linked article says it all - 39% of crime with 2% of police resource.