Many rules outlive the purpose for which they were intended. For example, there is a saying that Frederick the Great (1712-1786) lost the Battle of Jena (1806), meaning that for 20 years after his death the army perpetuated his successful (in his time) organization instead of adapting to meet the changes in the art of war. What rule, policy or way of thinking was successful for you in the past but may be limiting you now?