(p. 85) Carrying out a new plan and acting according to a customary one are things as different as making a road and walking along it.
Source:
Schumpeter, Joseph A. The Theory of Economic Development: An Inquiry into Profits, Capital, Credit, Interest, and the Business Cycle. Translated by Redvers Opie. translation of 2nd German edition that appeared in 1926; translation first published by Harvard in 1934 ed. New Brunswick, NJ: Transaction Publishers, 1983.