Why, having arisen on Earth, has been in constant development for billions of years?

Over millions of years of random attempts and chemical reactions, living matter appeared on our planet. This was the beginning of the development of life, which has been going on on our planet for more than one billion years. The goal of any living organism is to survive and produce offspring. In the course of evolution, new organisms appeared that played an important role in the ecosystem. Due to the wide variety of living things and the spread of life throughout the planet, even huge cataclysms did not destroy all life, and the remaining organisms continued to evolve and give rise to new species.