NIS 2012 Insight - Application Ratings question

Hi.

 

After running two Full System Scans about 5 days apart, I notice that the Files to Skip and Files to scan have barely changed.

 

10-4-2011 11-30-18 AM.png

 

Why would NIS not trust the remaining files to scan?

Is it because these files have not built a reputation yet in the community as of yet?

How long does this process take?

 

How can I make the scan time shorter without compromising security? Seems like a hard trade-off.

 

As usual TIA,

 

Atomic_Blast :)