What is seen:
electrons come instantly when light is turned on
there is no threshold in light intensity, and kinetic energy of the electrons independent of light intensity
there is a threshold in the frequency of the light to get any electrons, only the short wavelengths are effective, depending on the choice of metal (its work function W)
Big, big discrepancy. Einstein saw all would become clear if the quantum of light was really a particle, the photon, with energy