As companies move to the frontier, they can
often improve on multiple dimensions of per-
formance at the same time. For example, manu-
facturers that adopted the Japanese practice of
rapid changeovers in the 1980s were able to
lower cost and improve differentiation simul-
taneously. What were once believed to be
real trade-offs—between defects and costs, for
example—turned out to be illusions created by
poor operational effectiveness. Managers have
learned to reject such false trade-offs.