For there is one God, and one mediator between God and men, the man Christ Jesus
Easy. Read revelations where the prayers of the saints are offered to God in the form of sweet incense. Those prayers are to the saints for their intercession.
We are also instructed to pray for one another. Why don’t you tell the Jesus “why don’t you just pray directly to God”.
And what makes you think that if it isn’t explicitly written in the bible it’s forbidden, except for your Protestant tradition?
Y’all need to read more about “babbling of the pagans” because, using your logic, you couldn’t say a single prayer, including the Lord’s prayer, more than once.
I bet it’s just because the practice is Catholic and you have no idea what the Rosary truly is.