Agreed that password validation is the worst. (Github, I'm looking at you.)
Even worse than excessive validation is when they make you change your password often, for no apparent reason.
On some sites that do both (ahem Apple), the only way I can login if I haven't been there in awhile is the security questions or the password reset mechanism.
Wow, I never noticed that Github enforces password rules, as well (Must contain one lowercase letter, one number, and be at least 7 characters long.). My passwords are usually HMAC-based, so they'll most likely validate.
even validation of first & last names is usually awful. For instance many sites tell you that having a dash "-" in your first name is invalid... yet a lot of French (first or last) names contain that character..
Even worse than excessive validation is when they make you change your password often, for no apparent reason.
On some sites that do both (ahem Apple), the only way I can login if I haven't been there in awhile is the security questions or the password reset mechanism.