するする詐欺 (suru-suru sagi) — or やるやる詐欺 (yaru-yaru sagi) — literally means “do-do fraud”. Figuratively, it means that someone has repeatedly promised to do something soon but never does. In other words, it describes the behaviour of people who are all talk and no action. The duplicated verbs in this expression highlight the fact that one has promised to do something several times without ever carrying it out.
This idiom can be used for something either trivial or nontrivial. For instance, if you promise that you will propose to your girlfriend “one day” but never take any action, that’s a typical “結婚するする詐欺” (kekkon suru-suru sagi), meaning “do-do-marriage fraud”. Likewise, if you have promised many times that you will do your homework soon while you keep playing video games, that’s a common “宿題やるやる詐欺” (shukudai yaru-yaru sagi), “do-do-homework fraud” done by school kids.
In fact, する (suru) or やる (yaru) in this expression can be replaced by any verb depending on what is being procrastinated. For instance, Yuji Ayabe, a famous Japanese comedian, used to be criticized for his “行く行く詐欺” (iku-iku sagi, “go-go fraud”) because he had promised many times that he would leave for the U.S to become a Hollywood actor while procrastinating it for a very long time. (Although he eventually managed to keep his word, some people still cast doubt on his success overseas.)
Related Word: オレオレ詐欺 (ore-ore sagi)
Incidentally, オレオレ詐欺 (ore-ore sagi) is one of the most notorious frauds in Japan that are mainly targeted at elderly people. In this expression, オレ (ore) means “I” or “me”, which is also written as “俺” in kanji. Therefore, “ore-ore sagi” literally means “me-me fraud” and refers to the phone scam in which a scammer starts the conversation by saying “Hi, it’s me”, pretending to be a son or daughter of the targeted person. Typically, the swindlers plead with their “parents” to send them money, saying that they need a large amount of money immediately because they have accidentally got involved in financial trouble.
I’m fed up with your “お金返す返す詐欺” (okane kaesu-kaesu sagi; “pay-back-pay-back-money fraud”) = He has promised many times he would pay me back but never does.
My husband’s yaru-yaru sagi is too awful.
(This means that he always says he will do something soon but never does.)
Synonyms: 口先だけ, 口だけ: (all talk and no action)
Synonyms in English: all talk and no action, hot air
Related words and phrases: 詐欺 (fraud)