This can be observed at https://demos.telerik.com/kendo-ui/tilelayout/reordering : when you reorder the items, their "order" property changes, but their order in the HTML source stays the same. This makes the visual layout differ from the logical one.

The Sortable component, however, behaves correctly by reordering items in the HTML source.

See also: https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_Grid_Layout/CSS_Grid_Layout_and_Accessibility