After their commercial introduction, the number of producers of autos, tires, televisions,
and penicillin initially grew and then experienced a sharp decline or shakeout. Guided
by an evolutionary model of entry and exit, firm survival patterns in the four products
are examined to determine whether there were common forces governing their distinctive
evolution. Predictions concerning the effects of pre- and post-entry experience and
the timing of entry on firm survival are tested. The findings are used to reflect
on why industries experience shakeouts and evolve to be oligopolies.