Interpretting the Pages screen

Actions > Pages

I notice there is some permalink hierarchy built into the Pages view. For example, ‘Product A’ page would be featured under ‘Products’ page in a collapsible tree.

However, I also see that Product B, which is also under Products in the hierarchy, is listed outside of the tree in Piwik, as it’s own page.

I was wondering what causes this discrepancy and if there’s a way to keep things in their hierarchy?

UPDATE: I think the reason I was seeing this discrepancy is because I am hosting a WordPress site with posts and pages. The pages are hierarchical and the posts are not.