Resonance in ozone and benzene
This is because the electrons dont actually jump between the atoms of the molecule, but rather the electron cloud density is even distributed through the resonating bonds.  If atoms had to hold formal charges this would be very unstable for the electron count. In essence all of the resonant structures exist at the same time.  This lack of formal bonding in resonace is why benzene is often drawn as a circle inside a hexagon. This explaination does involve a bit of hand waving, and ignores higher level inorganic, but I think it should provide the needed additional clairity.