It is just a sequence of when to increase the bet size. It has nothing to do with luck. If you lose a bet and double your betting amount does it influence the next bet? It does not because the house edge remains same and it just a new bet every time, the seeds remain same.

It is easy to execute and thus popular and has become a stable first hand attempt at gambling by most newbies.

For the serious people here, use it when you have nothing else to use and still want to make some money from what you have left.