Model number?

Some drives like the early Conner SCSIs didn't support low level format by the user, since they had a system of assigning spare sectors for failing ones. Problem is, when all the spares are used up... and some just plain didn't work. There are some very advanced SCSI utilities which will permit you to roll your own non-standard commands and read the drive's response. One such is Siverlining, another is the SCSI Utility which can be found on some Mac developer CDs. Conner drives could only be formatted at the factory. Perhaps your Miniscribe is the same, though my memory is that they could be formatted in the field.

If the drive has been banged and the heads slapped the disk hard enough to dent it, the low level format is simply failing.