Origin gods are immortal. But they die permanently when they create their Supreme Law. Their previous self ceases to exist and is replaced by a law that thinks it is them.
The best they can do about this death is build the kind of law that they want to impersonate them. Now that they are trying to create a supreme law capable of acquiring information, they are literally dying for more knowledge.
They are determined about this because they learned a lot from Monarch High Heaven. The first thing they learned about was Aspects: how to create them and where they came from.
Monarch High Heaven had said, "The power of Aspects is independent of the void universe. It is a power that can be used in any universe regardless of its rules and laws. It is a power beyond the constraints of universes."
"Laws come from the universe. They are the manifestations of the order that gives shape to the universe and keeps it intact. They are acquired through comprehension."