Does the customer always lose?

The most effective way the casino makes money is- putting the capital to profit- the more guests visit the place the better the business is. Money that some guests lose "flow" to the guests who win , but some part of it stays in the pocket of the game organizer. This part depends on the type of the game, and it is the percent of the capital "flow"- the professional name for it is "house advantage" (casino`s predominance). According to mathematicians all casino games have "house advantage". Let`s not believe in those "absolutely certain systems"... see Game expected value

Black Jack is the exception. Here you can really ensure yourself with a little bit of predominance over the casino using appropriate systems. It means that not only will you have fun but you will make your starting capital a few percent bigger as well... see BlackJack Rules

But someone can ask: All right then, but why does the casino offer the game where it is likely to lose money? Well, the thing is that all Black Jack systems are very demanding- the player must have an incredibly good memory for figures. You are not allowed to write anything down at the table. What is more, to use the system efficiently you have to remember all the cards that have come down and at the same time do some complicated calculations in your mind concerning the present and future betting sums of money. We could see the players using this system in a marvelous film by Barry Levinson "Rain Man" with a fantastic part played by Dustin Hoffman. The main character`s superb mathematical and memorizing abilities allowed him to break the bank of a few game houses- even though he was autistic.