Virtuous circle and vicious circle

Virtuous circles (also called "positive feedback loops") and vicious circles (also called "negative feedback loops") are like patterns that help explain how things can become more and more successful (for a virtuous circle) or worse and worse (for a vicious circle).

A virtuous circle is like a snowball rolling down a hill. A small change in one place can cause bigger and bigger changes that all add together to help something become successful. For example, if a company creates a new product that lots of people buy, then the company can make more money which can help them make even better products which will make more people buy them and make the company even more money. It's like a snowball that just keeps getting bigger and bigger!

A vicious circle is like the same snowball rolling down a hill, but this time it keeps getting bigger and bigger but in a bad way. For example, if a person is always tired and so they don't have enough energy to do anything, they will become even more tired and it will be even harder to get up and do something which will make them even more tired, and so on. It's like a snowball rolling down a hill that keeps getting bigger and bigger, but in a bad way.