Can nonstop backup replace other backup methods?

Could somebody please tell me if Nonstop backup is a safe substitute for both regular file backups and partition images, or does it have limitations that would require me to also run regular scheduled file/image backups?

As far as I can see, nonstop backup has the ability to restore files just as you would from regular scheduled file backups, and restore complete partitions/drives as you would from a regular scheduled image backup.

I am a little confused because even though I have nonstop backup turned on and running, my acronis main page reports that my system is not fully protected because I haven't backed up my system.

Thanks in advance.