MarkR: Anyway, with all dishwashers, the mugs always have a pool of water on top of their bottoms. And we use a lot of mugs since almost everyone has a coffee or two each day. And that pool is never going to dry on its own. I keep trying to convince everyone to empty the bottom rack (plates, cutlery, etc) first, and then reverse all the mugs so they can drip down and actually eventually get dry. 
We have been using what started out as identical mugs for many years, my coffee is black no sugar so a quick rinse with only an occasional trip to the dishwasher does it. }};-D
Wife yucks hers up with milk and sweetener so there is little chance of mixing them up.
Meanwhile we have acquired lots of mugs that rarely get used unless company shows up. I would love to purge a bunch of them for the cupboard space as they don’t pay rent. Many don’t fit in our “Cup-at-a-time Coffee Maker” (not pods).
Oh I still have my Black and Gold Trump Mug that daughter bought me for babysitting her stupid mutt while she was stuck in Vegas at one of her husband’s trade shows. I used it to hold my tooth brush. We each have our own full bathroom in the condo … we don’t share well. }};-D
Tim