Why do things happen when they happen? Trigger analysis exposes the triggers that prompt sub-tasks to occur in the right order at the right time, and assess whether tasks are robust to interruptions, delays and shared responsibility. Trigger analysis starts with task decomposition via any suitable method, proceeding to uncover what trigger prompts each sub-task. The obvious answer: "because the previous sub-task is complete " is often the precondition, not the actual trigger. Previous analysis has uncovered certain primary triggers and potential failure points. The complete analysis produces an ecologically richer picture, with tasks interacting with and prompted by their environment
