TRIZ, or "theory of inventive problem solving," is a systematic approach to problem-solving that seeks to find the next evolutionary step. One principle of TRIZ is the idea that expensive or problematic items can be replaced with cheap, disposable alternatives. This has led to the development of many products that are designed to be used for a short period of time and then replaced. Gillette's razor blades are a prime example of this principle in action. By offering a cheap, disposable product, Gillette has created a lucrative business model that has been copied by many other companies. So, if you're looking for a cheap way to solve a problem, TRIZ might just have the answer.