Some people use the same (or similar) password with an add-on specific to the website. 

For example, the URL of this website starts with "proconnect".  So a person could use use the "pro" and set their password as "Password#1pro".  And their password for Amazon could be "Password#1ama".  That way you have your 'usual' password (in this example, "Password#1") and then just have that add-on for the website.

I think that originally ProSeries did not let you recycle passwords (or could not use something like your last five passwords), but apparently that has changed.