美国俚语:浪费时间和人力做某事却没效果

piss in the wind  浪费时间和人力做某事却没效果

英文解释:
Doing something that is a complete waste of effort and time for which you can expect no results and may even backfire on you.

中文解释：
是浪费时间和人力做某事却没效果，甚至适得其反。

例句：
Telling the president that invading other countries is unpopular with many voters is like pissing in the wind.
告诉总统侵略其他国家会遭到许多投票者的反对，那样的行为不会有好结果往往适得其反。