This will probably sound sophomoric, but I like Aristotle's answer to the question of purpose: that a living creature's purpose is to live the kind of life characteristic of its species, to the extent that it's able to. Whether or not there's more than that is a matter of philosophy and theology, but I think he does well enough proving that this is a bare minimum level of purpose for all living beings...

That seems to be an assigned purpose, where the will is attributed to some other process.

If a creature starts talking about having purpose, that usually means the creature's own purpose, not purpose assigned to it by something else.

I imagine nxc1 had the latter in mind, not the former.