What the Fallacy?!
The Gambler's Fallacy
The Fallacy
Believing that 'runs' occur to statistically independent phenomena such as roulette wheel spins.
Why it's wrong
This commonly believed fallacy can be said to have helped create an entire city in the desert of Nevada USA. Though the overall odds of a 'big run' happening may be low, each spin of the wheel is itself entirely independent from the last.
Example
After flipping a coin and getting heads five times in a row, Sarah bet her entire lunch money on tails, convinced that the universe had to 'balance things out' on the next flip.