What is the key factor determining a collapsing massive star’s fate: neutron star or black hole?

💡 Explanation:

The final fate of a massive star (forming a neutron star or a black hole) is primarily determined by the mass of the compact remnant core after the supernova explosion and significant mass loss. If the remnant core's mass exceeds the Tolman-Oppenheimer-Volkoff (TOV) limit (approx. 2.1 to 3.0 solar masses), the internal pressure (neutron degeneracy pressure) is insufficient to resist gravity, leading to the formation of a black hole. If the core mass is below this limit, it stabilizes as a neutron star.