What's wrong with the rhododendron not reproduced?

The cuckoo does not reproduce that it has not yet reached the breeding period, or the birds have no pairing, so they cannot lay eggs.This bird itself is not a nest, and there is no habit of breeding. Therefore, after mating, the female will produce her eggs into other bird's nests, and at the same time, they will take the other's eggs.The chicks often hatch faster than the parasitic birds. After birth, other bird eggs will be launched to enjoy the raising of righteous relatives.