The eternal jiva soul (a perpetual anti-material being) is only a passenger within a gross material bodily container or vessel, and that material vessel is part and parcel of the decomposing material creation.

Only every material bodily vessel or container eventually shows the effects of material impermanence, decline and decay that exists only in the temporary material universes.

Why?

Because the eternal jiva soul (a perpetual anti-material being) is only a passenger within a gross material bodily container or vessel, and that material vessel is part and parcel of the decomposing material creation.

Therefore because the jiva soul is NOT material (but anti-material), the jiva therefore NEVER dies.

However, the jiva is forced to change material bodies because each material vessel does not last forever likevthe jiva and eventually wears out.

This is due to the decay and decline eterally going on in the material creation which is the nature of the temporary material world.

Nothing is forever in the material world, everything eventually fades and passes away over time.

And because the material body grows old due to being in a constant state of decline, maintenance and decay, it eventually ceases to work at all and becomes unfit for the soul to remain.

Therefore the eternal jiva soul within the decomposing material body, is again FORCED to take another material bodily vessel out of 8, 400,000 species of life in the material creation.

The human form is very, very rare.

Most today will take birth in the lower species of life

This is how the jiva soul keeps experiencing the cycle of birth and death while in trapped in the material creation.