功亏一篑

功亏一篑

古时，有一个人要筑一座九仞（八尺=一仞）高的山。他堆了一年又一年，不论严寒酷暑，废寝忘食地从远处挖土，再挑土，再堆到山包上，终于有一天，他就要完工了。这一天也如往常一样，鸡刚叫就起床开工，一筐又一筐，眼看着山就要9仞高了，只差一筐土的工夫。但他一摸肚子咕咕叫，天又下起雪来，认为只有一筐土，就回家去了。此后，他总认为只有一筐土而偷懒，所以这一筐土至死他也没堆上，终究这座只差一筐土的九仞高的山还是没有堆成（为山九仞，功亏一篑）。“功亏一篑”一成语便出于此。

to fail to build a mound for want of one final basket of earth

Once a man planned to build a terrace. He worked very hard and spent a lot of time digging and carrying earth.
When the mound was almost completed and only one more basket of earth was needed, the man gave up. The terrace was never completed.
This idiom means to fail to succeed for lack of final effort. It has a connotition of pity.