Static vs Dynamic: Holywar in the rubbish chute

From a discussion at Not a kernel guy

The cafe trash bins are in groups of three pieces: for plastic, aluminum cans and the rest of the garbage. There are big icons on them so that no one would throw plastic can to the usual garbage bin. It would be nice but cleaners change bins places from time to time, which causes customer pain and frustration. Each person that has already raised arm to throw, hangs on for ten seconds, trying to understand what happened.

I laughed at the classification of the solutions offered in comments:

Static cast: You should have three bins of different shapes and make a stand with according slots then put them in a different order will be problematic.

Dynamic cast: You should stick the same icons opposite each bin then the cleaner would recognize these stickers and would think about the right order…

Duck typing: You should replace all bins of exactly the same without the icons, but put them on trays with icons (indicating the type of garbage) - ie indication of the type is external to the container =).