Array of blueprint object problem

I have an inventory that saves BP_Item in an array, why when I modify a BP_Item variable this change also on the variable of the object in scene? (variable are not set pass-by-ref)

Here a screenshot of what I was doing for testing purpose

if you change a variable on an object using a reference(pointer) it is the “original” object that is being modified. Pass-by-ref can be used to change the object that is passed in as a parameter without the need to return anything.

What are you trying to achieve exactly?