Keeping files on a redundant storage unit like a NAS is significantly safer than keeping them on your local PC drive, but the most common data loss isn’t the huge swaths of data when a drive fails, but when a single file is accidentally deleted or overwritten.

Having a backup that you can access quickly in these cases can save a lot of lost productivity when you have to recreate lost effort.  

A hybrid solution like DATTO is more complex than a simple backup program, but the addition of a local copy that you can restore quickly when someone inevitably deletes a file by accident can make your recovery a matter of minutes instead of hours.