This site has long understood that sandwiches always taste better when someone else makes them. It turns out there’s science behind this:

When you make your own sandwich, you anticipate its taste as you’re working on it. And when you think of a particular food for a while, you become less hungry for it later. Researchers at Carnegie Mellon University, for example, found that imagining eating M&Ms makes you eat fewer of them. It’s a kind of specific satiation, just as most people find room for dessert when they couldn’t have another bite of their steak. The sandwich that another person prepares is not “preconsumed” in the same way.

Via Tommy Bennett.