Running feed mills the insert screws comes loose before the insert life has expired. I think it is the main cause of insert failure. I found that every feed mill suffers from this issue. Iscar, Ingersoll, ZCC, Sumi and Kyocera all do it. I've taken to checking the insert screw torq at about half life of the insert and found that 80% of the time at least one screw has loosened. This policy has increased not only insert life but the life of the tool body. Why does this happen? Why is this so pervasive across all manufacturers? Most Importantly. What can be done to mitigate it other then stopping production to check for it?