A value of zero indicates
a completely inelastic market, where the new quantity supplied does not keep up with percentage changes in price.
The demand for energy is nearly
completely inelastic, their profit margins are more or less fixed, so higher energy costs simply apply their margin to an increased revenue base without them having to actually do anything more to earn the money!
Just consider the case where demand for fossil fuels is
completely inelastic.
Having
a completely inelastic demand for equities is a bit bonkers; no - one acts that way with life's other important commodities.
At the extreme, a ball colliding with silly putty — a plastic that is
completely inelastic — could lose almost all its kinetic energy.