There's the French expression -- which is used in English -- "raison d'être," which means something's reason for being, for existing at all.
Example: Art is the artist's raison d'être. (Maybe that's too romantic a use for you.)
A more common expression is "made for," as in "A shovel was made for digging." Or, "A woman was made to have babies." (LOL...a little dated humor, but still great.)