As lower cards are removed through play your chances of winning increase, in that blackjack becomes more likely as the remaining cards are more likely to be 10s-Ks, and pay bonuses, etc. As more and more high cards are removed and 2s-6s remain in the deck, the chances are more in the casinos favor. There is a point system assigned to cards. You have to remember the points to know whether or not to bet larger or smaller/double down/hit etc.