1) Part rejected during the first off part proving time due to wrong work offset calculation.|2) Tool offset need to be calculated from the machine bed and the rotary center need to be incremented and made zero but the operator made the machine bed as zero without increasing the rotary center.|3) Operator did not concentrated on the calculation and did not rechecked the offset values before running the part.|4) Operator was not aware of the offset crosschecking procedure.