Probably a small number of people can boast of being able to walk away from a casino with a winnings, and there are many more stories of failure. Risking your last remaining money is not a smart thing to do. I don't think such people have any strategy or plan of action for sure. It's just a huge success that happens very rarely, maybe even once in a lifetime.
True, it doesn't usually happen. It is totally on luck. However, it is not unusual to win small amounts of money here. As happened to Smith. But he gambled with $5,000 for about a week and won $17,000. This amount is not very high in gambling where many people have records of winning millions of dollars with keeping very few dollars.
Winning small amount of money in gambling should not be compared to other large winnings because it takes a bigger risks and large fund to win big earnings. For those gamblers we know now that are having big winning in gambling is as a result of the built confidence and experience so far. This is worth could trigger us to take bigger risk to gamble since we have enough fund to back ourselves up if in case any thing happens. Gambling is luck also and for those who had been taking risks, one day there luck might shine.