Ask your user to change the password after certain period of time is considered as one of the best security practices to increase the security. Few people argue that this feature is of no use , if someone steal your password they will do the harm and just get rid of your security grid. They are not going to stick around till you catch you, for eg someone steal your bank account password , hackers are going to transfer all the money right away so in that case that agrument makes sense too. However this feature can be handy for small business or personal websites or blog when hackers are slient not cozing any harm just stealing the information on regular basis by loggin to your account. If a business competitor gets access to certain business or paparazzi gets access to celebrity websites, they like to sneak in till you dont change the password.
So yes this features is good for small business and personal websites. To use the password aganing you need to go to Security Press >> General Settings >> Password Aging.
By Default it has value “0” which mean password will never expire. If you change the value other then “0” it will propt you to change the password in that many days from last login.