How NOT to stack a dishwasher

This is what I found in the office this morning, lots of cups stacked on top of each other sideways on...

Now rules of gravity would suggest the water cant flow in hit the dirty spot and flush back out ..... I am sure of it, well I know it really since I coudlnt put the cups away since they were filled with gunky water (a technical term i think).

I'm no physicist but hell even I know this much!
I'm not telling them anymore how to stack a dishwasher (since I dont have one of my own) but I did hand wash 12 mugs before being able to put them away.

I think I'll leave them to it in future and just let them drink the remnants of the dishwasher tablets.... lol

Well I'm not there everyday so I dont have to worry about it and I've started washing my own mug up at the end of the day just in case.....