1) Thickness got undersized beyond the drawing tolerance.|2) Thickness got undersized during the polishing operation.|3) 1.5mm thickness was maintained at minimum side during the machining completion and the part was not identified and separated at that stage.|4) Due to improper clamping the face did not properly butted and resulted in thickness to the minimum side. The part was sent for polishing because of the chatter marks caused due to machining strategy.|5) Due to the negligence of the operator the operator did not ensured the tightness of the part and the did not checked the thickness immediately after the completion machining.