cautionary tale

This term describes a narrative specifically designed to discourage a certain behavior by showcasing a disastrous outcome. It carries a didactic tone, where the primary purpose is moral instruction rather than mere entertainment. While a fable is a type of cautionary tale, the term "cautionary tale" is broader and can apply to real-life anecdotes, historical accounts, or modern news stories.

In professional or academic contexts, it is often used to describe a case study of failure. For example, a business that went bankrupt due to poor management is frequently cited as a cautionary tale for other entrepreneurs. It implies a lesson learned through the misfortune of others to avoid repeating the same mistakes.