Abstract: A system and method for manufacturing disk drives, the disk drives having reliability attributes and manufacturing attributes, the manufacturing attributes comprising process or component manufacturing attributes is disclosed. The reliability attributes comprise measurements for predicting future reliability of the disk drives at the time of manufacture. The disk drives are prepared with a servo format. Each disk drive is connected to a test apparatus and then tuned to verify that each disk drive performs within expected limits. One or more technical screen tests are performed on all of the disk drives. A first sample set of the disk drives is selected automatically at a defined size using a randomizer. One or more extended tests are executed on the first sample set of disk drives to measure a margin magnitude for one or more of the reliability attributes. The margin magnitude is compared with a reference to detect a significant change.