Evaporating Cloud and Future Reality Diagrams
The Evaporating Cloud refers to Goldratt's method for dealing with conflicts. In particular, Goldratt discusses the Core Conflict Cloud representing the Core Conflict in our CRT.
In an Evaporating Cloud Diagram, the end goal (aka the Systemic Objective) is placed in a box on the left. The two conflicting Prerequisite Conditions are placed in boxes at the right hand side of the drawing, with a lightning bolt arrow between them. The Necessary Conditions for the Systemic Objective are placed in boxes next to their respective conflicting prerequisite conditions.
The Evaporating Cloud Diagram illustrates the age-old conflict between upgrades and system stability. On the one hand, upgrades will increase the system reliability and performance. Neglecting upgrades for too long will eventually result in system problems. On the other hand, changes always carry some risk, so there is a strong desire to avoid the pain of changes, including upgrades.
In this case, we need to recognize the end goal of providing a reliable service. Upgrades need to be performed, but should be performed in a way that allows for adequate planning and testing in order to avoid introducing problems to a working system. This sort of solution "evaporates" the cloud.
We can use this solution to build a Future Reality Tree, which is like a Current Reality Tree, but with our solution injected into the diagram: