The law of entropy, presence of water, physical conditions of earth movement like volcanoes and atmospheric effects, and the stochastic, random interaction of elements on the Earth determined the degree of molecular assembly possible. The simple abiotic chemicals found in the water, on the land or distributed in the air, and deposited from meteors and comets show that at most some elemental biochemicals, including amino acids, simple sugars, lipids and polymers could form.
There are no naturalistic conditions or processes that could produce all the biochemical compounds and molecules required to assemble even the simplest living organism. Even in the lab, highly intelligent design and management of experiment processes and materials is required to produce interesting, but relatively minor, complex assemblies, but nothing comprehensive.
