つまらない (translations)→ bad bleak boring disappoint disgusting fool foolish fucking goddam horrible inadequate intolerable menial pedantic peewee prosaic rubbishy tedious unexciting uninteresting unreadable wearisome wretched zilch
徒労 (translations)→ futility mockery
無駄な (translations)→ boondoggling dud needless purposeless senseless unfruitful unproductive