目的地に向かって一部だけ行（い）ってやめれば、残りの一部は行けなかったから、結局目的地に行けない。だから一部行ったことまで無駄な苦労になる。
If you have a destination but stop after going only part of the way, you will ultimately fail to reach the destination because you did not travel the remaining portion. Therefore, even the portion that you did travel will be wasted effort.
photo: 「late on the pier」by Tim . Simpson from flickr