I guess I should say "appears haphazard" as I don't know if it really has been stacked with reckless abandon or of it's a kind of organised chaos as the two tend to look very similar. When your colleagues stack the dishwasher at work, they're adding to the load a little at a time until there's literally no room and someone has to run it. In such an instance there's no particular method to their madness other than fitting their one plate or one cup that they're personally trying to deal with.

When you're stacking a full load start to finish you're stacking with the aim of fitting everything you have from a large load of dishes of which really don't want to have any left out. In doing so, I at least, find that while one starts with some attempt at being organized, you'll eventually realise that if you just slightly lift this concave object slightly up so it's still upside down but not completely, you can squeeze this one awkward shaped small object in next to it, and this large flat but not very deep baking dish for which there is now no room on the bottom shelf will juuust fit if I kind of wedge diagonally a little and over the top some cups and small objects which hopefully will be small enough that some water can get between them and spray up and clean the baking dish. In the end it it can look like you put no thought in to it all but you know that you tesselated a 3d puzzle quite nimbly to squash the maximum possible number of dishes in there and then more often than not, despite all the fretting that certain types have over correct stacking, it ends up coming out much the same as when it's a lightly stacked load with optimal spacing. It definitely sometimes doesn't work out that way, but even then, in the absolute worst case scenarios where several dishes, not just one or two, didn't get all the way clean, you need only then unstack those that did clean fully and the remainders are already stacked ready for another cycle right away or to wait til later to make a fuller but hopefully not as full load.