Hersh Schefrin, a pioneer in the behavioral aspects of financial decision making, studies how a specific set of psychological traps snare decision makers, causing them to make inferior decisions. [Two] of the most common are excessive optimism [and] overconfidence. ... People learn to be excessively optimistic and overconfident. This means that successful people over-estimate their past successes, which feeds these biases. udging from the details of the case, show how these two forms of "bias" affected decision making at RIM. How might RIM's "inferior decisions" have been avoided if executives like Lazaridis and Balsillie had applied the steps in rational decision making