Psychology Today has an interesting article this month on why we get so attached to our favorite mugs. They offer six reasons, including the association with warm stimulating or soothing beverages, and the circumstances in which we use our mugs, which can have a ritual aspect. All of the reasons make sense, and I'd add this: the way in which we use mugs - with our hands wrapped around them - is more intimate and personal than the way we typically use plates or bowls.
And, let's not forget: some mugs are just objectively awesome! I threw some mugs today, hoping one or more or them will grow up to be somebody's favorite.
Architectural Digest profile of East Fork Pottery
44 minutes ago