The Hard Drive Recovery are done for many types of failures that occurs due electrical failure, write or read head failure, motor failure, head crash, firmware corruption, physical damages etc.
They involve many techniques and particularly when the data is not backed up and must be recovered. For retrieving the data from the damaged computer the drive may need to be moved to a working computer or need to open the drive an replace the parts like read / write heads, actuator arms, chips, etc.,
The Raid Recovery system works even when the hard drive fails. The RAID at this time operates in a critical state.
