What does the number of spots on the ladybugs' back indicate?

Coccinellidae is a widespread family of small beetles ranging in size from 0.8 to 18 mm (0.03 to 0.71 inches). The family is commonly known as ladybugs in North America and ladybirds in Britain and other parts of the English-speaking world. Entomologists prefer the names ladybird beetles or lady beetles as these insects are not classified as true bugs.

A common error, totally unfounded, is that the number of spots on the insect's back indicates its age. In fact, the underlying pattern and colouration are determined by the species and genetics of the beetle, and develop as the insect matures. In some species its appearance is fixed by the time it emerges from its pupa, though in most it may take some days for the colour of the adult beetle to mature and stabilise. Generally, the mature colour tends to be fuller and darker than the colour of the callow.