The most common approach taken by novice players is to play their hands according to the same rules the dealer must follow—i.e., to hit until their hand achieves a total of 17 or greater—figuring that this gives them as good a chance at the house of winning each round. This is, in fact, the sort of logic that the house counts on, and it is the basis by which they predict their income from the blackjack pits.
The loophole in this strategy, which gives the house its advantage, is that the player and dealer have an equal chance (33.15%) of busting—but when the player busts, he always loses, even if the dealer’s hand also busts. The odds of winning are shown in the table below:
In effect, the total chances for the player who follows house rules are only 39.75% to win (sum of all figures in green), a 9.59% chance to tie (blue), and a 50.71% chance of losing (red). This gives the house a 10.99% advantage over the player (scaled back to 8.9% when you consider a player wins 3:2 when he has blackjack and can opt to double, split, or surrender to improve his winnings or decrease his losses)—exactly the figure shown where the player and dealer both bust their hands.
In order to overcome the built-in bias of the game, a player must follow a strategy that departs from house rules when the dealer will bust, encouraging the player to stand on a total of less than 17. If it were possible to accurately predict when the dealer will bust, and to stand as a consequence,this would completely eliminate the house’s advantage and, by virtue of the same factors that decrease this edge (blackjack, double, split, and surrender),shift the odds in the player’s favor by roughly two percent.
To date, the most effective strategy devised is the basic strategy, discussed elsewhere on this site. While it is not perfect in its prediction of bust hands, it is as accurate as mathematical probability can possibly be, and enables the player to recoup his losses by doubling, splitting, or surrendering when it is most profitable to do so, reducing the house advantage to a razor-thin margin.
And so, while playing according to the house rules isn’t acutely bad, in and of itself, it’s not a particularly intelligent way to play your hand given the existence of a more profitable alternative.