Why does Hydra/Tiamat have 100% health regen?

Just an honest question. As someone that practically never uses the item and plays tanks or bruisers why should an item that grants massive aoe lifesteal have the same health regeneration as a tank item like. . Yeah health regen is kinda weak and will barely help you out but I feel like the item was designed for . Rejuvenation beads are also dirt cheap, 2 of them will match the regen on on most items. It just seems like a silly stat when its put on everything especially Hydra. I don't know if this is a rant about Hydra, health regen or my disgust for and when their hydra is complete.