Mottainai is a phrase ingrained in the Japanese language about being wasteful.
It expresses a feeling of regret if you waste food, resources or time.
It’s an all-purpose word that can be used in a strict way to get someone to finish their bento.
You can also use it in retrospect if someone didn’t take a chance to do something.
Mottainai is an old Buddhist word connected with the Shinto idea that inanimate and animate things all have souls.
Kenyan environmentalist and Nobel prize winner, Wangari Maathai, has used mottainai in her speeches about conservation since 2005.
She influenced The Mainichi newspaper and Japanese business firm “ITOCHU Corporation” to create a reducing, reusing and recycling project in Japan called mottainai.
You can check out their official site here.