Rule Of Three

there are many rules of three, but my favorite is: any plot which required more than three different things to happen would never work in real life (cf planning, HPMOR)

• cf Single Point Of Failure

another:

Johanna Rothman: Problem Solving with the Rule of Three - Create An Adaptable Life. The Rule of Three says that if I have just one solution it’s a trap, two solutions is a dilemma, and three solutions breaks logjam thinking and helps me think of more possible solutions.