  In previous work, based on work of Zwara and Yoshino, we defined and studied
degenerations of objects in triangulated categories analogous to degeneration
of modules. In triangulated categories it is surprising that the zero object
may degenerate. We study this systematically. In particular we show that the
degeneration of the zero object actually induces all other degenerations by
homotopy pullback, that degeneration of $0$ is closely linked, but not
equivalent, to having zero image in the Grothendieck group.
