Japanese idiom: Mikka Bozu (3 day monk)

In Japanese there are a lot of different idioms that you can use to make your language sound better.

One of the most used phrases that I have found, is this one.

三日坊主

It is often used in a self-deprecating manner.

When someone is unable to continue something that they set out to accomplish, they can refer to themselves as a "3 day monk"!

It can be used in funny way to tease someone gently as well.
When someone wants to quit something after not quite giving all their effort, you can gently tease them with this idiom.

But it has to be used with a smile - not with a sarcastic style, because sarcasm can be misunderstood in Japan!
So be careful!