This story tells us that people should not be ignorant of one's strength or doing something beyond one's ability.

这个故事告诉我们，人们不应该无视自己的能力，或者做超出自己能力的事情。

In short, people should understand their ability, don't attempt to do something far more beyond one's ability.

简言之，人们应该知晓自己的实力，不要企图去做远远超过自己能力的事情。

This idiom is used to mean overrating oneself and trying to do what is beyond one's ability. The result can be nothing but failure.

这个成语比喻高估自己去做自己能力以外的事情，这样的结果只有失败。