@ MartinL...

Yes i agree with you.  But when you limit the profit and exit at right time, chances are more to win. At least you may not lose more...

The problem with most of the gamblers are, they expect more profit.  They are tempted to play more and more.. Finally they end up losing it. 

To be successful, one should not play on the same site always.   Just make a small profit and exit from that site and play on a different site.  If we keep playing on the same site again and again finally we will lose the entire money.

Example:

Day 1 - Play at x site and exit with a minimum profit.. (may be 1 percent or 2 percent or 5 percent)...

Day 2 - Play at y site and exit with a minimum profit

Day 3 - Play at z site and exit with a minimum profit

Now we have loads of sites to play with...

Even by chance, if we lose 5 to 10 percent, just exit and don't play on that day..

Likewise, if we follow certain rules, atleast we will not lose more or make decent profit...