  The essence of the \textit{memory burden} effect is that a load of
information carried by a system stabilizes it. This universal effect is
especially prominent in systems with a high capacity of information storage,
such as black holes and other objects with maximal microstate degeneracy, the
entities universally referred to as \textit{saturons}. The phenomenon has
several implications. The memory burden effect suppresses a further decay of a
black hole, the latest, after it has emitted about half of its initial mass. As
a consequence, the light primordial black holes (PBHs), that previously were
assumed to be fully evaporated, are expected to be present as viable dark
matter candidates. In the present paper, we deepen the understanding of the
memory burden effect. We first identify various memory burden regimes in
generic Hamiltonian systems and then establish a precise correspondence in
solitons and in black holes. We make transparent, at a microscopic level, the
fundamental differences between the stabilization by a quantum memory burden
versus the stabilization by a long-range classical hair due to a spin or an
electric charge. We identify certain new features of potential observational
interest, such as the model-independent spread of the stabilized masses of
initially degenerate PBHs.
