Because each drive is have defect. The tag of each drive is very small. therefore chance that the error occurred. IBI team therefore is responsible for defect management of hard disk drive to make the user do not work on the defect.
Each package IBI team is the creator sequence file and parameter file up
For this reason, IBI team therefore the need to investigate the PTM and Parameter always correct. include investigate feature in each product so as to modified improve the sequence file and parameter file