String theory has not even come close to a complete formulation after half a century of intense research. On the other hand, a number of features of the theory suggest that the theory, once completed, may be a final theory. It is argued in this chapter that those two conspicuous characteristics of string physics are related to each other. What links them together is the fact that string theory has no dimensionless-free parameters at a fundamental level. The paper analyzes possible implications of this situation for the long-term prospects of theory building in fundamental physics.