The System is Initializing message that you are seeing is the newly introduced in Sitefinity 8.2 application status page: http://docs.sitefinity.com/overview-application-status-page
The reason you are seeing it is that the site is offline when you first access it. By default IIS will shutdown any site after 20 minutes of idle time. Once shutdown the first request to the site after that will bring it back up and thus cause Sitefinity to initialize.
You can increase the time before IIS shuts down the site by changing the "Idle Time-out (minutes)" property in the advanced settings of the application pool.
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