  Two relativistic models for collapsing spheres at different stages of
evolution, which include pre-relaxation processes, are presented. The influence
of relaxation time on the outcome of evolution in both cases is exhibited and
established. It is shown that relaxation processes can drastically change the
final state of the collapsing system. In particular, there are cases in which
the value of the relaxation time determines the bounce or the collapse of the
sphere.
