Frank Stewart 
Keys to Winning Bridge [EPUB ebook] 
The Advancing Player’s Handbook

Many elements contribute to success at bridge. Frank believes that two areas account for the difference between players who do well consistently and those who struggle. (1) A winning player has rock-solid fundamentals. The best part of an expert’s game is that he never — never — boots a simple situation. Give him a basic bidding problem or a textbook exercise in dummy play and he will get it right. If you never make errors in basic technique, you will have an edge over 90% of your competitors. (2) A winning player keeps avoidable errors to a minimum. Bridge is a game of mistakes. Nobody has ever played a perfect session, nobody ever will. Everybody makes mistakes. Winners make the fewest. This quote is attributed to Bob Hamman: "All players are poor players, including some good players." Hamman wasn’t being opprobrious; he was just acknowledging that we all have shortcomings. Many types of errors are common: mishandling suit combinations, forgetting to count, missing inferences. Maybe the majority of errors stem from lapses in concentration.