If 'create object' is false, the client doesn't send a createObject request to the server (XAS) when displaying the dataview with the create object propertie on false.
If 'create object' is true, the client does send a createObject request to the server (XAS), and the object is created (and has to role back on cancel) directly when opening a dataview with create object on true.
Example:
So if you have a dataview in a dataview and the object for the inner dataview is retrieved by microflow (triggerd by a button in de parent dataview) it's wisely to set the create object property to false. That aileth two requests, and so performs better.