Two people encounter the same unfamiliar material several times. One reaches accurate recall after relatively little exposure; the other needs more repetitions. Days later, however, their retention may look different again.

You answer a difficult question and feel only 55 percent confident. Instead of submitting immediately, you check your reasoning. On another question, you know that you do not know the answer and decide to look it up.

You need to arrive at an airport by 06:00. That goal alone is not a plan. You must work backward from departure time, estimate travel and security time, decide when to leave, arrange transport, identify dependencies and perhaps prepare alternatives if something goes wrong.

A strategy works repeatedly, and then the problem changes. The old strategy is still available—perhaps even automatic—but continuing to use it now produces the wrong result. Successful performance requires recognizing that the situation has changed and reorganizing what you are doing.