What did Kaku mean when he said 'assassins can never find other work'?


In the Enies Lobby Arc of One Piece, Kaku says to Roronoa Zolo 'they say
assassins can never find other work' after their fight.

[![An injured and defeated Kaku from One Piece saying 'they say assassins can
never find other
work'.](https://i.stack.imgur.com/TukPI.png)](https://i.stack.imgur.com/TukPI.png)

As a native English speaker, I have never heard this phrase be used before,
and a quick web search shows no results. This leads me to believe that it
could be a direct translation of a Japanese saying that had no English
alternative. But what does it mean?




The original [seems to
be](https://detail.chiebukuro.yahoo.co.jp/qa/question_detail/q1436058024):

> カク:パウリーか…。そうか…困ったわい…。殺し屋という仕事は **潰しがきかん** というのに…

潰しがきく essentially means that (the job) involves transferrable skills, or easy
to switch jobs/workplace. Here it is negated and the part literally means
"Being an assassin does not train you for other jobs (than assassins)" or
"Working as an assassin, I don't have skills for other jobs".

