Why do vampires feed their blood to a human?

For a vampire to feed a human their blood has many reasons. In most stories its how a human can become a vampire. The human has to be drained to the moment before death then fed the vampires blood. Another reasons is that vampire blood has strange magical and healing properties. It can heal a human of a wound. There is usually a level of intimacy and eroticism in the sharing of blood between vampire and human, childe and sire. However, some times there is a level of servitude. A person who drinks from a vampire can become addicted to the vampire, who will employ them as a ghoul or a familiar.

Vampires in the vampire diaries feed their blood to humans as it can heal them, plus if they die with the vampire blood in their system, they turn into vampires. In supernatural, vampires feed humans their blood to turn them into vampires. I only know about those two kinds of vampires lol

The human can become a Vamp, But~~ In other words, vampires also eat animals

It's believed to be like poison to humans and kill them so that they may rise again as a vampire

To make the otha person turn into a vampire