Hello,
Without context of where you saw this wording, we cannot respond to your question.
Here is a general answer.
The term "out of the box" means the product delivered "as-is" without any modification or customization. So when we say use "HOPEX out of the box" we mean that you use the standard solution such as BPA, ITPM... with standard/default metamodel, UX, workflows and reports.
As soon as you start to customize you are getting away from the "out of the box". Some customization and changes can be minor, some can be heavy.
I hope this answer help.
