What distinguishes a core-collapse supernova scenario resulting in a 'no remnant' outcome?

The explosion energy was high enough to completely eject all material, or the resulting black hole is undetectable.

In specific cases involving highly massive progenitor stars, the gravitational collapse of the core can be so complete that the explosion energy either ejects every particle of the star, leaving behind no central compact object, or the resulting remnant is a black hole that is too faint or obscured to be easily observed against the background radiation. Differentiating this true 'no remnant' scenario from one where an unobservable black hole or neutron star exists is a significant challenge in astrophysics, often requiring long-term monitoring to confirm if the shell continues expanding without influence from a central engine.