Explain why the color of the ladybug is called warning?

The ladybug is a small but very useful beetle (it eats aphids) that anyone has known since childhood. If you touch a ladybug, it releases a yellow liquid. This liquid is very caustic, and if the bird tries to eat the beetle, this liquid will burn its mouth and it will spit out the cow. And, next time, you won’t try to eat it. Because birds will remember its bright color. That is why such a coloring is called warning, it seems to say: “Don’t eat me, I’m not edible.”