Some pallet block patterns are the same for the entire height of the pallet, while others are reversed as the pallet is built. The same pattern process is called column stacking and the reversal technique is known as cross-stacking or interlocking. Cross-stacking of boxes or packages on a pallet adds stability to the pallet with a balanced weight load.
By cross-stacking boxes pallets are more stable which helps to promote better transport and unloading procedures.
http://porkycow.com/how-to-cross-stack-boxes-or-packages-on-...

As an alternative to stacking, cross-stacking of trays is done by rotating a top tray 90 degrees about a vertical axis and lowering it onto a lower tray or trays (see FIG. 14). Cross-stacking is often used to improve the stability of trays of bottles loaded on a warehouse pallet. In a cross-stacked structure, each layer has trays oriented parallel to each other with the trays in adjacent layers being oriented at right angles to each other. Since each tray in the cross-stacked layer rests on at least two trays in the layer below, the trays of the cross-stacked layer tend to keep the trays on which they rest from moving apart from each other, thereby stabilizing the structure.
http://www.google.hr/patents/US7549539

Most importantly, however, the present container not only can be conveniently nested with identical containers but also can be cross-stacked, i.e., interlocked in a square configuration thereby producing a very stable unitary stack of containers.
https://www.google.com/patents/US3393827

Interlocking the packages (cross stacking) is universally practiced to stabilize pallets. ...
https://books.google.co.jp/books?isbn=1118352637

For the most secure load, cross stack your cartons, boxes, or bags. When the direction of each tier of cartons or bags is alternated, the load is said to be interlocked or cross-stacked. This method of loading allows each carton or bag, except for the top and bottom, to be in contact with at least two cartons or bags above and two below.
https://www.gluefast.com/products/skid-lock-adhesives.html