Under what condition does a collapsing stellar core inevitably form a black hole?

Answer

The remaining core mass exceeds the limit capable of being supported by neutron degeneracy pressure

If the remnant iron core mass is too great, even the immense force of neutron degeneracy pressure cannot stop the collapse. The gravitational compression continues indefinitely, resulting in the formation of a black hole.

Under what condition does a collapsing stellar core inevitably form a black hole?
evolutionhydrogenCorestarFusion