If you know a password generation algorithm, you can compute a lower bound on the average time to crack a password given that it was generated by that algorithm

If you know a password generation algorithm, you can compute a lower bound on the average time to crack a password given that it was generated by that algorithm. Some individual password might happen to get unlucky, but you can still have a good general idea of the strength of a password if you know the set it was drawn from and the distribution.