Three Rolls, One Decision, and 14/3
A die is rolled up to three times and you are paid the face you stop on. The reflex answer of 3.5 is the value of the same game with the right to stop deleted, and the real value is 14/3, reached by computing the game from its last roll backwards. The thresholds move as rolls run out, which is why a four is worth keeping late and worth rejecting early.