Site maturity is length of time that a web site has been operational or registered to an owner. The site maturity is measured by the number of days since the site was launched and the time to expiration.
Site maturity is a ranking factor for certain search engines (including Google). It is assumed that the age of the site is an indirect measure of the authority of the site or business.
This is a factor that site owners have no control over. The only way to influence this is to purchase a long standing site or to 'hang-in' with your current site.