I'm not sure why this happens but it does and I'm not sure what I do to change it. Typically when working I am able to work on the desktop layer and move objects onto the page layer seamlessly. Vice versa, I'm able to move from the page to desktop. For whatever reason, sometimes when I'm working on the desktop layer, if I create a new object or move an object from a page layer, that object will remain on the page layer and will not transition to the desktop layer. The only way around it is to either group all of the objects on the desktop layer and ungroup them or cut and select the Desktop layer and paste into it. I don't know what I do to change this behavior because typically when starting a document it works as expected. Thanks.
Have you unchecked keep desktop objects on layer?