[RichDad]

Playing roulette betting on red or black.

He has $1000.
He bet $15 each time.
If he lose he double his bet. $15, $30, $60,$120,$240,$480
Once he win he starts betting $15

This is what happened .

tried before, need lots of capital and discipline, know when to stop. But casinos got limits, you can't keep doubling up.

Can win a bit, if you are lucky. Most of the time, you quit after losing.