Why are avatars or great saints considered to be beyond the cycle of birth and death?

Chapter 43 explains that avatars and great saints are not bound by the conventional cycle of birth and death because they are fundamentally different from ordinary beings. They are described as the 'personification of the form of Brahman' who incarnate by their own will with the sole purpose of ensuring the welfare of devotees. Since they are manifestations of the Supreme Brahman, for whom the material world is an illusion, the physical body is just an 'adjunct' and not their true identity. The text states, 'The states of birth and death never come to avatars.' When their specific task is completed, they don't 'die' but simply merge back into their true, unmanifest form, a process they control at will.