Not necessarily. If people work locally then copy to a central repository if the repository craps out you should have the latest out there somewhere, much better chance of data recovery then than if everything lives exclusive in the repository.
I've seen Raid 10, it all lives and dies by the parity disk, if the parity disk lives you can reconstruct your data with otherwise massive disk loss, but the parity disk is the key to recovering the data, no parity equals major uh oh.
So rather then properly architect a data storage solution you want to depend on the cheapest disk dell can send you? this would not pass in an enterprise environment.
ummm Raid 10 has no 'parity disk'. Raid10 is either s mirror of stripes or a stipe of mirrors. Raid 4/5 and some of the more exotic ones you might see on a dell array or an e series box from IBM use parity, and usually they allow redundant parity. Other raids which do use parity disk now can have more than one, and you're still ignoring hot swaps.
Quick example: I have two raid fives which are mirrored, each raid 5 has two hot disk, how many disk can I lose?
In addition to all the above the disk used in network storage devices are usually on (1) always on, (2) on UPS, and (3) of higher quality than what dell might send you in a desktop. All of this means the failure of any given raid disk is far less likely than the failure of the disk in your pee-cee.