Overview#Password Quality is the degree resistance to a password value from being obtained by an Unauthorized entity (ie an Attacker)
Generally "Truly" random passwords are better than any other methods. Also the longer a password is the better.
Password-composition policies must strike a balance between maximizing security and maximizing Usability. Generally results indicate that, as might be expected, increases in Password Quality (ie entropy) often correlate with a decreases in usability.
- Brute-Force of submitting various password to an Identity Provider (IDP) until the correct Password is discovered.
- Heuristic Attacks
More Information#There might be more information for this subject on one of the following:
- [#1] - Of Passwords and People: Measuring the Effect of Password-Composition Policies - based on information obtained 2017-04-08-
- [#2] - Secure Passwords Keep You Safer - based on information obtained 2017-01-02