Imagine you go to a breakfast buffet, and you realize at the end of your feast that your eyes were way bigger than your stomach. You’re left with a perfectly good croissant, a whole scoop of scrambled eggs and untouched slices of fresh fruits that are all headed for the bin because you cannot fathom another bite (i.e. you’re stuffed).
Practically any Japanese person will describe your situation as “mottainai”, which basically means, “it’s a shame that so much food is going to waste”. This sense of regret or guilt over waste is encompassed in this single word.
People in Japan are raised not to be “mottainai” as much as possible, often cleaning up each meal down to the last grain of rice! While it may seem a little intense, it reflects the deep-rooted Japanese spirit of respect–not just for the food itself, but for the effort that went into preparing it.
Learn more about the mottainai spirit: https://www.japanlivingguide.com/living-in-japan/culture/mottainai/