Case in point
I spoke to the head of small company – about 25 employees – who had suffered a RAID5 drive failure. The 4TB RAID was used for file sharing.
A drive failed, reconstruction failed and vendor phone support was disastrous. All data was lost.
But the worst of it was that there was no backup. They believed that RAID5 would protect their data. They were wrong.
What RAID5 is for
RAID5 does offer some data protection assuming it works. But it's main purpose is to protect access to your data. This is why it is popular in enterprise applications where maintaining data access during a failure is of vital concern.