From [When would you use the Builder Pattern?](https://stackoverflow.com/questions/328496/when-would-you-use-the-builder-pattern),

It is said that builder pattern is appropriate for Pizza example.

Why not Decorator ?
by treating Cheese, Pepperoni, Bacon as additional decorations on a base pizza.

Is it for the reason that Cheese/Pepperoni have to be built seperately. I don't think, they need to be built seperately as they can be available readymade.

Pls clarify.
Am also looking for a good real-world example of decorator pattern and reason why it is the apt for that particular example. Thank you.