Life Cycle Approach to Competitive Advantage
Rita Gunther McGrath and Ian C. MacMillan in MITSloan Management Review Vol 50 No 3 mention the term
Transient Competitive Advantage. I looked up the term "transient" and it means "valid for a limited time". The authors do not see Competitive Advantage as an ON/OFF phenomenon (in which you either have a competitive advantage or you don't), but as a
wave, following a kind of
product life cycle, with following phases: Launch, Ramp up, Exploitation and Erosion.
During the wave your
competitive advantage varies in strength: it is weak in the beginning (launch and ramp up) then strong (exploitation) and then declines again (erosion).