無為無能
mu.i.mu.nou

Literally: nothing – do/benefit – nothing – ability

Alternately: Not doing anything, and not able to do anything. A complete lack of action, and of ability to achieve anything significant. Idle and incompetent.

Notes: Keep in mind that despite the obvious application in contemporary American politics, in Japan this expression is most likely to be used about oneself, as a humble expression of modesty.

And then there’s this yutz.