Learn Chinese with @cn-reader Idiom: 一颗老鼠屎, 坏了一锅粥
成语：一颗老鼠屎,坏了一锅粥
Idiom: A speck of mouse dung spoils a whole pot of porridge.
熬了一锅粥，结果发现粥里面居然有一颗老鼠屎，当然这锅粥自然是不能吃了。比喻因为一个人的问题，结果牵连了整个群体。
If you found a mouse dung in a pot of porridge, what would you do? Dump it, of course unless you want to poison yourself. It implies to irresponsible behavior of one person could potentially affect the whole team.
这样的例子非常多。比如前一阵子非常热闹的乌托邦翻译。很多会双语的人都在那段时间通过贡献翻译，得到很多的奖励。可是由于有一些人非常不自觉，使用电脑软件翻译，或者胡乱翻译一通，完全不顾翻译的质量，给审稿人带来了很大的困扰。而且给项目方也带来很不好的影响。在经过多次的规则修改还是无法得到很好的成效也遏制这种行为后，最后，乌托邦决定完全不支持翻译的贡献。
You will be able to find many examples that would fit to this idiom. If you remember clearly, utopian-io used to support translation contribution. Many people who is bilingual benefited a lot from Utopian’s reward. But some people tried to take advantage of the system, they used machine translation and submitted very poor work. The poor quality not only let to extra workload of moderators, and brought a lot problems to the project team. After modifying the rules for few times, utopian-io finally decided to stop supporting translation all together.
在那些翻译大军里，其实是有很多优秀的人在贡献优质的内容，可是由于那些人的行为，导致这些优质的贡献者也失去这么一个非常好的挣钱机会，对于一些第三世界的国家，这其实是很不错的工资来源。这就是一个典型的 发生在我们身边的一颗老鼠屎,坏了一锅粥 的故事。在英文里有类似的说法，不同的是他们用的是坏苹果。一粒烂苹果坏了一篮子。
No doubt there were many good translators and good works, however, due to the difficulty to curb the inappropriate behavior by some people, all translators lost the great opportunity to make extra money. For some 3rd country people, it could have been a decent income source. This is a typical case that just happened around us. In English, there is a similar saying, but they used apple instead. One rotten apple spoils the whole barrel.