 According to one theory proposed by the "Nihon Gogen Daijiten", the term comes from the Japanese expression , where the literal meaning of the phrase "matter of chance", , is "a matter of water".In the entertainment business, income depends on a large number of fickle factors like popularity among customers, the weather, the state of the economy; success and failure change as rapidly as the flow of water.The "Nihon Zokugo Daijiten", on the other hand, notes that the term may derive from the expression , lit.