There are many different ways to categorize motives for murder. After ‘Be in Control’ I break the flowchart down to Power, Passion & Revenge. There are many subcategories after that, with the inevitable crossover between the three main one. I’ve produced charts to cover these for a book on mystery cluetrails that I am writing. The main purpose is to give writers some inspiration on what drives a person to kill. Here’s the chart for Power.