Synopsis: The 5 Whys is a simple problem-solving technique that helps users to get to the root of the problem quickly. Brainstorming was made popular in the 1970s by the Toyota Production System, the 5 Whys strategy involves looking at any problem and asking: "Why?" and "What caused this problem?" Very often, the answer to the first "why" will prompt another "why" and the answer to the second "why" will prompt another and so on; hence the name the 5 Whys strategy.