Why do we continually fall for the temptation of get rich quick?

It’s because our money choices are primarily motivated by our instinctual caveman brain. Unfortunately evolution has optimized our very out-of-date brain for the problems faced by hunter-gatherers. When our caveman ancestors made a kill, it was important that they gorge themselves. Why? Because they might not find food again for a long time.

So what happens when we have a win in the market? Our instinctual brain compels us to buy more. We do this at the worst time, when that investment is most likely to be overvalued and primed for a fall.