I don’t have a collection, I have three. Three are easy to keep up with. The plan is to use one. The second is dirty and probably in the dishwasher. The third is clean, sitting in the cupboard. Do you think that works? There must be some flaw in the system when all three wind up dirty and in the same place.
For years, lots of years, over a couple of decades, I only had one. It had a daily cycle. A.M., coffee. Early afternoon, tea. Evening beer. Rinse if necessary, repeat.
A while back, 7-8 years ago, Kari found another in a local consignment store. It’s the one in the back left of the photo. That same day, I had an armload of stuff that I was too lazy to make a second trip out to the car for and I had both mugs in one hand while trying to open the door to the house. Gee, guess which one slipped from my hand, fell, and broke. Not the one in the picture.
I have a couple of spares now. The only time I’ll carry more than one at a time is when all three wind up "dirty and in the same place." Then I’ll carry them to the kitchen, carefully.
Maybe I’ll put coffee in the one that already had coffee in it. The other already had tea in it, why not use it again for tea? I’m not sure what was in the third one. I’ll wash it. 
Ein stein coffee, please.
Put it in a dirty mug
I’ll drink to your health.
Peace, Y'all!
da6d