A Chinese proverb 螳螂捕蝉, 黄雀在后 (tang2 lang2 bu3 chan2, huang2 que4 zai4 hou4). A warning not to get too proud or smug with one's successes (or perceived successes) to forget or ignore any danger that lurks.

The story behind this proverb is quite easy to understand, and can be observed in the wild. As the praying mantis slowly approaches the unsuspecting cricket, it is unaware that a sparrow is behind him, only waiting for it to pounce on the cricket before it gobbles both up.

(Killing two insects with one peck! Clever bird.)

This proverb also refers to those who lack perspective and who focus only on plans to rip off other people, and forget that there are others plotting to profit from him as well. (The underlying message is to be street smart and to guard your back as well.)