It indicates the full progress, from beginning to end, of a process, which, at the end, will return to the original position or condition

You helped me when I needed it and now I'm helping you, so things come full circle

Quando avevo bisogno tu mi hai aiutato ed ora io aiuto te, e così il cerchio si chiude

He was living in a car when he won the lottery, then he threw away all his money on women, drugs and bad investments; eventually he came full circle: he's living in a car again

Quando ha vinto la lotteria viveva in un'automobile, poi ha sperperato tutti i soldi in donne, droga e investimenti sbagliati; ora ha chiuso il cerchio e vive ancora in un'automobile