  Interactions of electron spins with rotational degrees of freedom during
collisions or with external fields are fundamental processes that limit the
coherence time of spin gases. We experimentally study the decoherence of warm
cesium spins dominated by spin rotation-interaction during binary collisions
with N$_2$ molecules or by absorption of near-resonant light. We report an
order of magnitude suppression of the spin decoherence rate by either of those
processes at low magnetic fields. We find that the excess decoherence at higher
magnetic fields originates from an asynchronous Larmor precession, which is a
mechanism that universally affects all alkali atoms, and can yet be suppressed
at low magnetic-fields. This work extends the widely-used regime of
Spin-Exchange Relaxation Free (SERF), which provides protection from
decoherence by random spin-conservative processes, now for random processes
which do not conserve but rather destruct electron spins.
