On the way, he was killed-suddenly, playing the zodiac? Seeking an optimal solution?

Because it ranks second in the zodiac.

There is a story that the Jade Emperor told all the animals one day that whoever goes to Tianmen first will be in charge of the years on earth. Cows are the most industrious animals. It got up first that day and reported there. The mouse said, "Niu Ge, that's very kind of you. Please give me a ride!" " The old cow said nothing, "All right!" They talked and laughed all the way. As he approached Tianmen, the mouse suddenly said, "Niu Ge, this is not good for the people. Look, there are other animals catching up behind. " Without saying anything, it looked back and there was no one at all! The mouse immediately jumped down and ran to Tianmen. In this way, rats rank first, and steaks rank second. Later generations also used shortsightedness and rat brain to describe people's cunning, and your true stubbornness to describe a person's recklessness and stubbornness.