Expect the best, but be reasonable. People make mistakes, and accidents will happen. You are a living, caring, compassionate, reasoning person, not a machine. Be efficient, but be reasonable.
Every situation is different.
Solve problems rather than just handling them. Cure the cause and not just the symptom. You have the wonderful ability to reason. If you pretend not to be able to reason people will see though the charade and it will only hurt you in the end. Use your mind to determine when to make an exception.